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2SQLTechnical Reference Guide

Version 5.4.0

February 2014

© 2014 ConvertU2 Technologies Pty Ltd in conjunction with CU2 Global Pty Ltd. All rights

reserved.

ConvertU2, CU2, and 2SQL are either registered trademarks or trademarks of ConvertU2 Technologies Pty Ltd in Australia, the United States and other countries. Access and SQL Server are trademarks of Microsoft Corporation.

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Table of Contents

INTRODUCTION .......................................................................................................................................................... 8

CONVERSION CATEGORIES BY COMPONENT .............................................................................................................. 9

TABLE SCHEMA (FIELD TYPES).............................................................................................................................................. 11

Text Field Types ........................................................................................................................................................ 11

Memo Field Types .................................................................................................................................................... 11

Date Field Types ....................................................................................................................................................... 11

Date Based Unique Indexes ...................................................................................................................................... 11

Boolean Field Types .................................................................................................................................................. 12

AutoNumber Field Types .......................................................................................................................................... 12

Integer Field Types ................................................................................................................................................... 12

Long Field Types ....................................................................................................................................................... 12

Decimal Field Types .................................................................................................................................................. 12

Long Binary Field Types ............................................................................................................................................ 12

GUID Field Types ...................................................................................................................................................... 12

Currency Field Types ................................................................................................................................................. 12

Single Field Types ..................................................................................................................................................... 12

Double Field Types ................................................................................................................................................... 12

Byte Field Types ........................................................................................................................................................ 12

Attachment Field Types ............................................................................................................................................ 12

TABLE SCHEMA (CONSTRAINTS) ........................................................................................................................................... 13

Table Relationship Field Size Conflicts ...................................................................................................................... 13

Table Relationship Field Type Conflicts .................................................................................................................... 13

Column Validation Rule Syntax ................................................................................................................................ 13

Column Default Value Syntax ................................................................................................................................... 14

Table Relationship Deletions .................................................................................................................................... 14

Column Format Properties ....................................................................................................................................... 14

InputMask Properties ............................................................................................................................................... 14

TimeStamp Columns ................................................................................................................................................ 14

Column DisplayControl Properties ........................................................................................................................... 14

Nullable Boolean Fields ............................................................................................................................................ 14

Nullable Boolean Fields without Default Value ........................................................................................................ 14

Memo Fields with Validation Rules .......................................................................................................................... 14

Disallow Zero Length String Constraints .................................................................................................................. 15

Disallow Zero Length Memo Constraints ................................................................................................................. 15

TABLE SCHEMA (INDEXES) ................................................................................................................................................... 16

Primary Key Indexes ................................................................................................................................................. 16

Unique Indexes ......................................................................................................................................................... 16

Non Unique Indexes ................................................................................................................................................. 16

Tables with Unique Index but no Primary Key .......................................................................................................... 16

Tables with no Unique Index and no AutoNumber .................................................................................................. 17

AutoNumber Tables with no Unique Index .............................................................................................................. 17

Clustered Indexes ..................................................................................................................................................... 17

Indexed Memo Fields ............................................................................................................................................... 17

Composite Primary Keys with Autonumbers ............................................................................................................ 17

Nullable Unique Indexes ........................................................................................................................................... 17

TABLE DATA ..................................................................................................................................................................... 18

Invalid Date Values .................................................................................................................................................. 18

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Duplicate AutoNumbers ........................................................................................................................................... 18

Null AutoNumbers .................................................................................................................................................... 18

Unindexed Required Fields with Null Values ............................................................................................................ 19

Unique Indexed Required Fields with Null Values .................................................................................................... 19

Orphaned Table Relationship Records ..................................................................................................................... 19

Data Migration......................................................................................................................................................... 19

Table RowCount Reconciliation ................................................................................................................................ 19

SQL STATEMENTS (A TO E) ................................................................................................................................................. 20

Aggregate SELECTs ................................................................................................................................................... 20

Alias Name References ............................................................................................................................................. 21

Boolean Expressions ................................................................................................................................................. 21

Boolean Sorts ........................................................................................................................................................... 21

Bracketed Joins ........................................................................................................................................................ 21

Cartesian Joins ......................................................................................................................................................... 21

Crosstab Syntax ........................................................................................................................................................ 21

DATEADD String Comparisons.................................................................................................................................. 22

Date Based Comparisons ......................................................................................................................................... 22

Date based DISTINCTs .............................................................................................................................................. 22

Date Based GROUP BYs ............................................................................................................................................ 22

Date Based Joins ...................................................................................................................................................... 23

Date Expressions ...................................................................................................................................................... 23

Date Functions using Dynamic Interval Parameter .................................................................................................. 23

Date Functions using FirstDayOfWeek Parameter ................................................................................................... 23

DELETE Statement Syntax ........................................................................................................................................ 23

Deterministic BETWEEN Clause Comparisons .......................................................................................................... 23

DISTINCTs with Foreign ORDER BY Expressions ....................................................................................................... 24

DISTINCTROW Selects .............................................................................................................................................. 24

Double Quotation Usage .......................................................................................................................................... 24

Duplicate Column Aliases ......................................................................................................................................... 24

Duplicate ORDER and GROUP BY Expressions .......................................................................................................... 25

Dynamic Aliases ....................................................................................................................................................... 25

Encapsulated Table Column Expressions.................................................................................................................. 25

Exclamation Mark Usage ......................................................................................................................................... 25

EXISTS Functions with Boolean Reference ................................................................................................................ 25

SQL STATEMENTS (F TO N) ................................................................................................................................................. 26

Floating Point Divisions ............................................................................................................................................ 26

Functions Requiring Data Type Conversions ............................................................................................................ 27

Implicit SELECTs ........................................................................................................................................................ 27

HAVING Clauses with no GROUP BY Clause ............................................................................................................. 27

Implicit Sorts Using DISTINCT ................................................................................................................................... 27

Implied Boolean Comparisons .................................................................................................................................. 27

Implied Boolean Expressions .................................................................................................................................... 28

Implied Form/Report Control Input Parameters ...................................................................................................... 28

Implied Input Parameters ........................................................................................................................................ 28

Linked SubForms ...................................................................................................................................................... 28

MakeTable Statement Syntax .................................................................................................................................. 29

Memo based DISTINCTs ........................................................................................................................................... 29

Memo Based GROUP BYs ......................................................................................................................................... 29

Memo Based Function Parameters .......................................................................................................................... 29

Memo Based Joins .................................................................................................................................................... 30





Memo Based ORDER BYs .......................................................................................................................................... 30

Missing Keys in SELECT Clauses ................................................................................................................................ 30

MOD Operators ........................................................................................................................................................ 30

Multiple Object Updates .......................................................................................................................................... 30

Non Deterministic BETWEEN Clause Comparisons .................................................................................................. 31

Non Text Based Concatenations .............................................................................................................................. 31

Numeric Alias and Object Names ............................................................................................................................. 31

SQL STATEMENTS (O TO Z) ................................................................................................................................................ 32

OLE/HyperLink based DISTINCTs .............................................................................................................................. 32

OWNERACCESS OPTION ........................................................................................................................................... 32

Query Names Longer than 60 Characters in SQL ..................................................................................................... 33

Reserved Key Word Usage ....................................................................................................................................... 33

Rounded Divisions .................................................................................................................................................... 33

SELECTS requiring WITH TIES ................................................................................................................................... 33

SELECTs with ORDER BY ........................................................................................................................................... 33

Square Bracket SELECTs ........................................................................................................................................... 33

String Concatenation Symbols ................................................................................................................................. 33

Superfluous DISTINCTs ............................................................................................................................................. 33

Superfluous ORDER BY and GROUP BY expressions ................................................................................................. 33

Superfluous Semi Colons .......................................................................................................................................... 34

TABLE SELECT Clauses .............................................................................................................................................. 34

TimeStamp Column Exclusion .................................................................................................................................. 34

UNIONs with Object Name in ORDER BY Clause ...................................................................................................... 34

UNIONs with Superfluous ORDER BY Clause ............................................................................................................ 34

UPDATE Statement Syntax ....................................................................................................................................... 35

User Defined Input Parameters ................................................................................................................................ 35

Wildcard References ................................................................................................................................................ 35

XOR Operator ........................................................................................................................................................... 35

VBA FUNCTIONS (A TO D) .................................................................................................................................................. 36

ASC Function ............................................................................................................................................................ 36

CCUR Function .......................................................................................................................................................... 36

CDATE Function ........................................................................................................................................................ 36

CDBL Function .......................................................................................................................................................... 36

CHOOSE Function ..................................................................................................................................................... 37

CHR Function ............................................................................................................................................................ 37

CINT Function ........................................................................................................................................................... 37

CLNG Function .......................................................................................................................................................... 37

CSNG Function .......................................................................................................................................................... 37

CSTR Function ........................................................................................................................................................... 37

CURRENTUSER Function ........................................................................................................................................... 37

CVDATE Function ...................................................................................................................................................... 37

DATE Function .......................................................................................................................................................... 37

DATEADD Function ................................................................................................................................................... 37

DATEDIFF Function ................................................................................................................................................... 37

DATEPART Function.................................................................................................................................................. 38

DATESERIAL Function ............................................................................................................................................... 38

DATEVALUE Function ............................................................................................................................................... 38

DAVG Function ......................................................................................................................................................... 38

DAY Function ............................................................................................................................................................ 38

DCOUNT Function .................................................................................................................................................... 38





DLOOKUP Function ................................................................................................................................................... 38

DMAX Function ........................................................................................................................................................ 38

DMIN Function ......................................................................................................................................................... 39

DSUM Function ........................................................................................................................................................ 39

VBA FUNCTIONS (E TO M) ................................................................................................................................................. 40

FIRST Function .......................................................................................................................................................... 40

FIX Function .............................................................................................................................................................. 40

FORMAT Function .................................................................................................................................................... 40

FORMATCURRENCY Function ................................................................................................................................... 41

FORMATDATETIME Function ................................................................................................................................... 41

FORMATNUMBER Function ...................................................................................................................................... 41

FV Function .............................................................................................................................................................. 41

HOUR Function ......................................................................................................................................................... 41

IIF Function ............................................................................................................................................................... 41

INSTR Function ......................................................................................................................................................... 41

INSTRREV Function ................................................................................................................................................... 41

INT Function ............................................................................................................................................................. 41

IPMT Function .......................................................................................................................................................... 41

ISNULL Function ....................................................................................................................................................... 42

LAST Function ........................................................................................................................................................... 42

LCASE Function ......................................................................................................................................................... 42

LEFT Function ........................................................................................................................................................... 42

LEN Function ............................................................................................................................................................ 42

LTRIM Function ........................................................................................................................................................ 42

MID Function ............................................................................................................................................................ 42

MINUTE Function ..................................................................................................................................................... 42

MONTH Function ...................................................................................................................................................... 42

VBA FUNCTIONS (N TO Z) .................................................................................................................................................. 43

NOW Function .......................................................................................................................................................... 43

NZ Function .............................................................................................................................................................. 43

PARTITION Function ................................................................................................................................................. 44

PMT Function ........................................................................................................................................................... 44

PPMT Function ......................................................................................................................................................... 44

PV Function .............................................................................................................................................................. 44

RIGHT Function ........................................................................................................................................................ 44

ROUND Function ...................................................................................................................................................... 44

RND Function ........................................................................................................................................................... 44

RTRIM Function ........................................................................................................................................................ 44

SPACE Function ........................................................................................................................................................ 44

STR Function ............................................................................................................................................................. 44

STRCONV Function ................................................................................................................................................... 44

STRING Function ....................................................................................................................................................... 44

STRREVERSE Function............................................................................................................................................... 44

TIME Function .......................................................................................................................................................... 45

TRIM Function .......................................................................................................................................................... 45

UCASE Function ........................................................................................................................................................ 45

User Defined Function References ........................................................................................................................... 45

VAL Function ............................................................................................................................................................ 45

WEEKDAY Function .................................................................................................................................................. 45

YEAR Function .......................................................................................................................................................... 45





SQL SERVER OBJECTS ........................................................................................................................................................ 46

Table Creation .......................................................................................................................................................... 46

Append Stored Procs ................................................................................................................................................ 46

Update Stored Procs ................................................................................................................................................. 46

Delete Stored Procs .................................................................................................................................................. 46

MakeTable Procs ...................................................................................................................................................... 46

CrossTab Procs ......................................................................................................................................................... 47

Select and Union Views ............................................................................................................................................ 47

CrossTab Views ........................................................................................................................................................ 47

User Defined Function Templates ............................................................................................................................ 47

UPDATE Triggers for Tables ..................................................................................................................................... 47

DELETE Triggers for Tables ....................................................................................................................................... 47

INSERT Triggers for Tables ....................................................................................................................................... 47

INSTEAD OF INSERT Triggers for Tables ................................................................................................................... 48

INSTEAD OF DELETE Triggers for Views ................................................................................................................... 48

INSTEAD OF UPDATE Triggers for Views .................................................................................................................. 48

INSTEAD OF INSERT Triggers for Views .................................................................................................................... 48

Foreign Key Constraints ........................................................................................................................................... 48

Check Constraints ..................................................................................................................................................... 48

Default Value Constraints ........................................................................................................................................ 48

Virtual Table RowCount Reconciliation .................................................................................................................... 48

ODBC CONNECTION OBJECTS ............................................................................................................................................. 49

ODBC Links to Tables ................................................................................................................................................ 49

ODBC Links to Views ................................................................................................................................................. 49

ODBC Indexes ........................................................................................................................................................... 49

Pass-Through Queries .............................................................................................................................................. 49

APPLICATION FRAMEWORK ................................................................................................................................................. 50

Aggregate Functions in Form Controls ..................................................................................................................... 50

Form/Report ControlSource Syntax.......................................................................................................................... 50

ControlSource Syntax of Report GroupLevels ........................................................................................................... 51

Form/Report ORDER BY Properties .......................................................................................................................... 51

Form/Report RecordSource Properties .................................................................................................................... 51

Form/Report RowSource Properties ......................................................................................................................... 51

Form/Report ControlSource Properties with Input Parameters ............................................................................... 52

Query Names Longer than 60 Characters ................................................................................................................ 52

Query Metadata ....................................................................................................................................................... 52

Table Metadata........................................................................................................................................................ 52

Updatable Forms with Read Only Recordsets .......................................................................................................... 52

Parent Table Key Changes from Forms .................................................................................................................... 53

Child Table Key Changes from Forms ....................................................................................................................... 53

Form Controls bound to Tables with Default Values ................................................................................................ 53

2SQL Toolkit Objects ................................................................................................................................................ 53

OPTIMIZATION OF DATA OBJECTS ......................................................................................................................................... 54

Domain Functions .................................................................................................................................................... 54

RunSQL Usage .......................................................................................................................................................... 54

Code Alerts ............................................................................................................................................................... 56

DAO RecordSet Variable Declarations ..................................................................................................................... 56

DAO RecordSet Instantiations .................................................................................................................................. 56

DAO RecordSet Properties ........................................................................................................................................ 57

DAO Executes ........................................................................................................................................................... 58





DAO DBEngine Commands ....................................................................................................................................... 58

ADO RecordSet Instantiations .................................................................................................................................. 58

Obsolete DAO Usage ................................................................................................................................................ 58

CurrentProject Connections ..................................................................................................................................... 58

VBA FRAMEWORK ............................................................................................................................................................ 59

CloseQuery Calls ....................................................................................................................................................... 59

OpenQuery Calls ....................................................................................................................................................... 59

OpenForm Calls ........................................................................................................................................................ 59

OpenReport Calls ...................................................................................................................................................... 59

OpenQuery SetHostValue Calls ................................................................................................................................ 60

OpenForm SetHostValue Calls .................................................................................................................................. 60

OpenReport SetHostValue Calls ............................................................................................................................... 60

Queries Longer than 60 Characters in VBA Code ..................................................................................................... 60

DEPLOY TO PRODUCTION ENVIRONMENT ............................................................................................................................... 61

Recreate Table Objects and Data ............................................................................................................................. 61

New Table Objects ................................................................................................................................................... 61

HostName Tables ..................................................................................................................................................... 61

User Defined Functions ............................................................................................................................................ 61

Views ........................................................................................................................................................................ 61

View Triggers ........................................................................................................................................................... 61

Stored Procedures .................................................................................................................................................... 62

Pseudo Index Table Data .......................................................................................................................................... 62

2SQL VERSION HISTORY .............................................................................................................................................63





Introduction

This technical guide describes each of the “conversion issues” that 2SQL identifies and

automatically addresses. Not every issue appears in every database, but if it does, it

must be dealt with for the new Microsoft Access/SQL Server application to behave and

function as expected. Some of the conversions are very basic and do not require a

detailed explanation. Others are quite complex. Examples are given to describe how

and why 2SQL deals with them.

There are several documents published by Microsoft and other companies which

provide a basic technical understanding of converting and migrating Microsoft Access to

SQL Server. However, our research and testing has uncovered many additional

conversion issues which were not documented anywhere. All of these issues and

methods to remedy them have programmed into 2SQL or documented in our process.

It is assumed that the reader of this document possesses a comprehensive knowledge of

Microsoft Access and SQL Server programming. It should also be noted that whilst there

is considerable detail in this document, readers are cautioned against using this

document as an exclusive source to attempt to convert an application manually.

Theexamples provided do not reflect the entirety of the methodology by which 2SQL

programmatically analyses existing syntax and applies its modifications.

This Technical Reference Guide should also be read in conjunction with the 2SQL

Functionality Overview document, the 2SQL User Guide, the 2SQL Conversion Services

Guide and all 2SQL Toolkit Documents. Together with 2SQLand support from ConvertU2,

these technical documents will take the reader through an entire conversion project

from start to finish.

____________________________





Conversion Categories by Component

This next section lists and describes each of the Conversion Categories in each

Conversion Component that 2SQL automatically identifies and remediates.The “2SQL

Conversion Issue, Complexity and Manual Estimation Report” screen below is a

summary of all Conversion Categories by Conversion Component, from a scan of a highly

complex sample database by 2SQL in Detective mode. See the 2SQL Functionality

Overview document for more information about the results of this scan and the value

proposition that 2SQL offers.





The following sections include 2SQL screen shots showing details of Issue Count, Rating

and Conversion Elements by Conversion Category for each of the Conversion

Components.

Although these sectionsalso explain the Conversion Issue and a corresponding solution,

it does not explain how to find the issue in the first place or the potential cascading

effect that the remedy has on the rest of the application. 2SQL's ability to scan, analyse,

and remedy every single property of the objects in the Access database automatically

addresses these concerns as well.

It should also be noted that the Conversion Issues in each Category can exist in far more

permutations than the examples provided. 2SQL is programmed to anticipate and

remedy all possible permutations.





Table Schema (Field Types)

Text Field Types

2SQL will convert table fields of type Text to the SQL Server Varchar type with its

corresponding field length.

Memo Field Types

2SQL will convert table fields of type Memo to the SQL Server Text field type. Memo

field types can circumstantially be converted to varchar(max), but the SQL Server Native

Client ODBC drivers do not fully support varchar(max) when the length of the field is

greater than 255 characters. The Native Client driver will return a field of type memo

back to the Access front end if the SQL Server field type is Text. This is the main reason

why 2SQL converts Memo to Text.

Date Field Types

2SQL will convert table fields of type Date to the SQL Server DateTime type. The minute

and second components of each date value are also preserved.

Date Based Unique Indexes

2SQL will convert table fields of type Date to the SQL Server Date type instead of

DateTime whenever it belongs to a Unique index. This ensures that the index occurs at





the day level, like it does in Microsoft Access. However, this conversion category is only

used with SQL Server 2008 solutions.

Boolean Field Types

2SQL will convert table fields of type Boolean (Yes/No) to the SQL Server Bit type.

AutoNumber Field Types

2SQL will convert table fields of type AutoNumber to the SQL Server Integer type with

the Identity property set to true and seed value 1 increment value 1.

Integer Field Types

2SQL will convert table fields of type Integer to the SQL Server SmallInteger type.

Long Field Types

2SQL will convert table fields of type Long Integer to the SQL Server Integer type.

Decimal Field Types

2SQL will convert table fields of type Decimal to the SQL Server Decimal type with

corresponding precision and scale.

Long Binary Field Types

2SQL will convert table fields of type Long Binary to the SQL Server Image type.

GUID Field Types

2SQL will convert table fields of type GUID to the SQL Server UniqueIdentifier type.

Currency Field Types

2SQL will convert table fields of type Currency to the SQL Server Money type.

Single Field Types

2SQL will convert table fields of type Single to the SQL Server Real type.

Double Field Types

2SQL will convert table fields of type Double to the SQL Server Float type.

Byte Field Types

2SQL will convert table fields of type Byte to the SQL Server SmallInteger type.

Attachment Field Types

2SQL will convert table fields of type Attachment to the SQL Server Varbinary(max) type.





Table Schema (Constraints)

Table Relationship Field Size Conflicts

If the source column of a table relationship is a field of type text and differs in size to the

foreign column, 2SQL will increase the size of the smaller field to the larger.

Table Relationship Field Type Conflicts

If the source column of a table relationship is of a different field type to the foreign

column, 2SQL will calculate which field type takes precedence, and make them both the

same field type.

Column Validation Rule Syntax

Table Column Validation Rules will have their column name included in the formula if

the AND/OR clauses are used. For example:

>= 100 AND <= 200

Becomes

[columnname] >= 100 AND [columnname] <= 200





Column Default Value Syntax

2SQL will convert default value specific syntax to its SQL Server Equivalent. For example,

a default value of GENGUID() will be converted to NEWSEQUENTIALID(). Otherwise,

2SQL will generate a dummy SQL Statement SELECT clause using the default value as the

first field, and pass it through all the SQL Statement conversion rules, and create a SQL

Server Default Constraint. See the component called SQL Statements in this document

for more information.

Table Relationship Deletions

2SQL will delete all Table Relationships in the Access database. These are converted to

SQL Server Foreign Key Constraints later in the conversion process. See the component

called SQL Server Objects in this document for more information.

Column Format Properties

2SQL will copy the Format property of Table Columns to their corresponding linked

Table Object equivalent.

InputMask Properties

2SQL will copy the InputMask property of Table Columns to their corresponding linked

Table Object equivalent.

TimeStamp Columns

2SQL will add a timestamp column called RowVersion to each table migrated to SQL

Server. This is done to assist the SQL Server Native Client ODBC connection record

locking methods.

Column DisplayControl Properties

2SQL will copy the DisplayControl properties of Table Columns to their corresponding

linked Table Object equivalent. The following properties are copied:-

DisplayControl ListWidth Rowsource RowSourceType

BoundColum ColumnCount ColumnWidth ColumnHidden

ListRows LimitToList

Nullable Boolean Fields

If the Column of a Table is originally of type Boolean that allows nulls, 2SQL will enforce

the column NOT to allow nulls. This is because Microsoft Access treats Null Boolean

fields as False. See the category directly below for more information.

Nullable Boolean Fields without Default Value

Further to the category directly above, if the Column of a Table is originally of type

Boolean that allows nulls and there is no default value, 2SQL will enforce a default of 0.

Memo Fields with Validation Rules

The equivalent to a field of type Memo in SQL Server is Text, which does not allow Check

Constraints, so 2SQL will create Triggers on the table that serve the same purpose as the

Access Validation Rule.





Disallow Zero Length String Constraints

When the AllowZeroLength property of a field of type String/Text is true, and there is no

validation rule, 2SQL will create a CHECK constraint in SQL Server that checks the length

of the field.

Disallow Zero Length Memo Constraints

When the AllowZeroLength property of a field of type Memo is true, and there is no

validation rule, 2SQL will create Triggers on the table that serve the same purpose.

Triggers are required because the equivalent SQL Server column of type Text will not

allow a CHECK constraint.





Table Schema (Indexes)

Primary Key Indexes

2SQL converts Microsoft Access Primary Key Indexes to SQL Server Primary Key indexes.

Unique Indexes

2SQL converts Microsoft Access Unique Indexes to SQL Server Unique indexes. Columns

belonging to Unique Indexes that are not composite ones will be set not to allow null

values irrespective of the value of the Required Property of the table column, so long as

the data in the table does not conflict with this condition. If null values are detected in

the data columns of such unique indexes, 2SQL will not create the corresponding unique

index in SQL Server, and log this issue as an alert for review post conversion.

Non Unique Indexes

2SQL converts Microsoft Access Duplicates Allowed Indexes to SQL Server Non Unique

Indexes.

Tables with Unique Index but no Primary Key

Tables with unique indexes but none of them being a primary key are usually an

oversight of schema design and can cause confusion. There is no reason why one of the

unique indexes cannot be a primary key. Both Access and SQL Server look for the

primary key of a table over any unique index to identify and process unique rows of a

table. When 2SQL encounters such tables it will make the first unique index a primary

key.





Tables with no Unique Index and no AutoNumber

Tables without a Unique Index become read only tables when they are linked to SQL

Server from the Microsoft Access front end. When 2SQL encounters tables without a

primary key, it will add an autonumber column with a naming convention of

TableName_ID for the column name. 2SQL will then add a primary key to this column as

per the conversion category directly above.

AutoNumber Tables with no Unique Index

Tables without a Unique Index become read only tables when they are linked to SQL

Server from the Microsoft Access front end. When 2SQL encounters tables of this nature

but also with an autonumber column, it will add a primary key to the

autonumber/identity column, thereby making the table updateable from the front end.

Clustered Indexes

2SQL will identify the Microsoft Access Unique index that can become clustered and set

the clustered property of the corresponding SQL Server Index to true.

Indexed Memo Fields

Fields of type Memo get converted to the SQL Server Text field type by 2SQL. However,

Text field types in SQL Server do not support indexing. 2SQL will recognize this and

bypass creating the index in SQL Server.

Composite Primary Keys with Autonumbers

When 2SQL detects a table with an autonumber column as part of a composite primary

key, it will remove all other columns and make the autonumber the singular primary

key. Although this is a design issue more than a conversion issue, doing so avoids

complications when the need for troubleshooting occurs.

Nullable Unique Indexes

Microsoft Acccess allows Unique Indexes on nullable fields where the data can have

multiple null values. SQL Server does not. 2SQL will create INSTEAD OF Triggers that

serve the same purpose as these Nullable Unique Indexes.





Table Data

Invalid Date Values

Date fields in Access tables with less than January 1 1753 or greater than December 31

9999 will be modified to a value of January 1 1753 by 2SQL. These date values are the

lowest and highest respectively for SQL Server columns of type datetime.

Duplicate AutoNumbers

Tables with AutoNumbers that do not have a unique index can potentially have

duplicate autonumber rows. Such tables are corrupt in Microsoft Access and are caused

by known bugs in Access itself. 2SQL will detect and remove duplicate autonumber rows

so as to avoid violation errors that would otherwise prevent 2SQL from migrating the

data of such tables to SQL Server.

Null AutoNumbers

Tables with AutoNumbers that do not have a unique index can also potentially have null

autonumber rows. Such tables are corrupt in Microsoft Access and are caused by known

bugs in Access itself. 2SQL will detect and remove null autonumber rows so as to avoid

violation errors that would otherwise prevent 2SQL from migrating the data of such

tables to SQL Server.





Unindexed Required Fields with Null Values

It is possible for Microsoft Access fields that do not allow nulls to actually have null

values. Such data is in conflict with the schema and will prevent the entire table from

being migrated to SQL Server. When this occurs on fields that do not belong to a unique

index and there is no validation rule, 2SQL will set fields of type string/memo to an

empty string, date fields Jan 1 1753, and numeric fields to zero. A warning message alert

will also be logged to trigger a review during the cleanup phase of the conversion

project.

Unique Indexed Required Fields with Null Values

Further to the category directly above, if the field belongs to a Unique Index 2SQL will

remove the culprit rows from the table because these rows are in conflict with the table

schema. A warning message alert will also be logged to trigger a review during the

cleanup phase of the conversion project.

Orphaned Table Relationship Records

It is possible for Microsoft Access to have orphaned records in Table Relationships. 2SQL

will remove such records because they are in conflict with the table schema. A warning

message alert will also be logged to trigger a review during the cleanup phase of the

conversion project.

Data Migration

Once the Table schema has been converted and migrated to SQL Server, 2SQL will

migrate all of the data in all Microsoft Access Tables to their corresponding SQL Server

Tables.

Table RowCount Reconciliation

2SQL will reconcile the row counts of the original Access Table and the corresponding

SQL Server table after migration. Row counts that match are treated as a successful

reconciliation. Rowcounts that do not match are treated as an error requiring manual

review.





SQL Statements (A to E)

Aggregate SELECTs

JET allows a SELECT statement to be a parameter of an Aggregate Function. SQL Server

does not. 2SQL will restructure the syntax of the SELECT clause and the aggregate

function to a working equivalent. For example,

MIN(SELECT numfield FROM tablename)

Becomes

(SELECT MIN(numfield) FROM tableName)





Alias Name References

Column Alias Names that are referred to before or after they are defined in the SQL

Statement are replaced with the corresponding Alias Definition. For example:-

SELECT A*B AS C,C*D AS E

Becomes

SELECT A*B AS C, A*B*D AS E

Boolean Expressions

Boolean Values of Yes, True, On, and -1 are converted to a value of 1.Boolean Values of

No, False, and Off are converted to a value of 0.

Boolean Sorts

Sorting by a Boolean field in Microsoft Access in ascending order will display Boolean

values of True before False, but in SQL Server False values will display before True

values. 2SQL will automatically reverse the sort order for Boolean Sorts in the ORDER BY

clause.

Bracketed Joins

2SQL will remove the brackets of JOINS encapsulated with left and right round brackets

to ensure compilation in SQL Server.

Cartesian Joins

When 2SQL detects a Cartesian Join it will add the CROSS JOIN predicate because not all

Cartesian Joins will compile in SQL Server without this predicate.

Crosstab Syntax

2SQL Converts Access CrossTab Queries that have an IN Clause to SQL Server Views.

CrossTabs that do NOT have an IN Clause are converted to Stored Procedures. In both

cases, the entire SQL Statement is restructured to use the SQL Server PIVOT clause. For

example:

TRANSFORM Sum(table1.amount) AS SumOfAmount SELECTtable1.field1,table1.field2

FROM table1 GROUP BY table1.field1,table1.field2 PIVOT table1.field2 In ("A”,"B")

Becomes

SELECT * FROM (SELECT table1.field1,table1.field2,table1.amount FROM table1) p

PIVOT (Sum(p.amount) FOR p.field2 IN ([A],[B]) ) AS pvt





DATEADD String Comparisons

When 2SQL identifies string based Date expressions used in the DATEADD Function, it

will implement the 2SQL Toolkit Function FormatDateSQL to return the date in Short

Date Format in order to reflect Microsoft Access functionality when applying

computations to string based date expressions.

Date Based Comparisons

JET compares dates at the day level, and SQL Server compares dates at the millisecond

level. 2SQL converts date comparisons to use the DATEDIFF Function. For example:-

SELECT F1 FROM TableName WHERE DateField1 = DateField2

Becomes

SELECT F1 FROM TableName WHERE DATEDIFF(dd,DateField1,DateField2)=0

When date fields are part of a Non Deterministic BETWEEN clause, 2SQL will implement

its built in function called BETWEENDATES2SQL to simplify the syntax. See the category

called Non Deterministic BETWEEN clauses for more information.

Date based DISTINCTs

If 2SQL has already converted a SELECT DISTINCTROW to SELECT DISTINCT, it may refer

to fields that were originally of type Date. To enforce DISTINCT processing at the day

level instead of the millisecond level, 2SQL will use the CONVERT function with a style of

106 as follows:-

SELECT DISTINCT datefield FROM Table1

becomes

SELECT DISTINCT CONVERT(varchar(max),datefield,106) FROM Table1

Date Based GROUP BYs

Date Based fields that reside in the SELECT clause and are used in the GROUP BY clause

of a SQL Statement are grouped at the day level in Microsoft Access. In SQL Server, the

grouping occurs at the millisecond level. 2SQL will encapsulate such date based fields

with the CONVERT function using a style of 106. For example:-

SELECT T1.DateVal, SUM(T1.NumVal) FROM T1 GROUP BY T1.DateVal

Becomes

SELECT CONVERT(varchar(max), T1.DateVal), SUM(T1.NumVal) FROM T1 GROUP BY

CONVERT(varchar(max),T1.DateVal,106)





Date Based Joins

Joins referring to fields of type Date do a Join at the day level in Microsoft Access. In SQL

Server, this occurs at the millisecond level. 2SQL will implement the DATEDIFF function

at the day level for date based joins to enforce day based date joins. For example:

SELECT * FROM Table1INNER JOIN Table2 ON Table1.F1 = Table2.F1

Becomes

SELECT * FROM Table1 INNER JOIN Table2 ON DATEDIFF(dd,Table1.F1,Table2.F1)=0

Date Expressions

The Hash (#) symbol is replaced with a single quote for dates that are expressed as

literal strings.

Date Functions using Dynamic Interval Parameter

When 2SQL Detects Date functions with dynamic interval parameters it will implement

the corresponding built in 2SQL Toolkit Function that accepts this parameter dynamically

and applies the calculation. This is because SQL Server Date Intervals must be strongly

typed.

Date Functions using FirstDayOfWeek Parameter

When 2SQL Detects Date functions that use the FirstDayOfWeek Parameter it will

implement the corresponding built in 2SQL Toolkit Function that includes

FirstDayOfWeek calculations. For example the DATAPART function will be replaced with

DATEPART2SQL.

DELETE Statement Syntax

DELETE Statements that use the asterisk (*) symbol representing all columns of a Table

or Query will have this part removed. References to individual columns are also

removed.

DELETE Statements that refer to JOINS in the FROM Clause will be restructured to refer

specifically to the Table/View that will have rows deleted from it. For example:

DELETE * FROM T1 INNER JOIN T2 ON T1.F1 = T2.F1

Becomes

DELETE T1 FROM T1 INNER JOIN T2 ON T1.F1 = T2.F1

Deterministic BETWEEN Clause Comparisons

The compare parameters of a deterministic BETWEEN clause are swapped around if the

second compare parameter is less in value than the first compare parameter.





DISTINCTs with Foreign ORDER BY Expressions

SELECT DISTINCT clauses that refer to columns in the ORDER BY clause that are not part

of the DISTINCT clause are converted to a Table Alias. For example:

SELECT DISTINCT F1,F2 FROM T1 ORDER BY F3

Becomes

SELECT DISTINCT DerivedTable.* FROM (SELECT TOP 9999999 F1,F2 FROM T1 ORDER BY

F3) DerivedTable

DISTINCTROW Selects

The DISTINCTROW predicate of a SELECT statement is removed if it is an updateable

one.

DISTINCTROW SELECTS that refer to JOINS, but also refer to one or more columns from

each of the JOIN objects in the SELECT clause, are converted to normal SELECT

statements.

DISTINCTROW SELECTS that do not refer to JOINS are converted to normal SELECT

statements (i.e., DISTINCTROW is completely removed).

Otherwise, DISTINCTROW is converted to DISTINCT.

Double Quotation Usage

All double quotes are converted to single quotes.

Duplicate Column Aliases

Microsoft Access deals with Duplicate Column References in several different ways

subject to the content of the SQL Statement, as follows:

1. Ignores the reference completely so that it does not display and cannot be referred to by other SQL Statements. 2SQL will remove the duplicate reference.

2. Creates an alias of value Expr101x on the fly, where x is a number from 0 to 9. 2SQL determines when this occurs and adds an alias of the same name to the duplicate column reference.

3. When a column of the same name belongs to two (or more) objects, and both instances are referred to in the SELECT clause, Microsoft Access JET will dynamically name them as table1.columnname and table2.columnname, without aliases. Although it is possible to create columns with full stops in SQL Server, they cannot be referred to from Microsoft Access by way of linked tables, so 2SQL will create an alias of TableName_ColumnName in such instances. 2SQL will also address the cascading effect this has on other SQL Statements that refer to them by way of nested queries.





Duplicate ORDER and GROUP BY Expressions

2SQL will remove any duplicate reference in ORDER and GROUP BY clauses. Superfluous

in JET, it is not tolerated in SQL Server T-SQL. For example:

SELECT * FROM TableName ORDER BY F1,F2,F1

Becomes

SELECT * FROM TableName ORDER BY F1,F2

Dynamic Aliases

When the field of a SELECT clause is a computed expression without an Alias Name, JET

will create one dynamically at run time. 2SQL will detect these occurrences and add the

Alias to the computed expression permanently in the SQL Statement.

For example:-

SELECT NOW()

Becomes

SELECT GETDATE() as [Expr1001]

Encapsulated Table Column Expressions

References to [ObjectName.ColumnName] are converted to

[ObjectName].[ColumnName]

Exclamation Mark Usage

Expressions that use the exclamation mark to refer to the column of a query or table are

replaced with a full stop. For example:

TableName!ColumnName

Becomes

TableName.ColumnName

EXISTS Functions with Boolean Reference

References to EXISTS compared to True will have the comparison to True removed.

References to EXISTS compared to False will have the comparison to False removed and

replaced with NOT EXISTS.





SQL Statements (F to N)

Floating Point Divisions

JET Returns a data type of Double when performing divisions in SQL Statements. With

SQL Server, it returns the data type of the dividend component of the divide. When the

data type of the dividend is NOT of type FLOAT, 2SQL will encapsulate the dividend with

CONVERT(float,..) .





Functions Requiring Data Type Conversions

SQL Server Functions such as SUM are strict in their usage of data types. For example:

SUM(nonnumericfield)

Becomes

SUM(CONVERT(integer,nonnumericfield))

2SQL applies various checks to various functions and implements the CONVERT function

where necessary.

Implicit SELECTs

The asterisk symbol can be used in SELECT clauses as a shortcut to display all columns

belonging to a table or query. However, the columns will need an explicit reference if

any kind of conversion on them is required due to other conversion categories. In such

instances, 2SQL will remove the asterisk and replace it with an explicit reference to all

columns of the SELECT object(s).

HAVING Clauses with no GROUP BY Clause

The criteria of the HAVING clause needs to be moved to the WHERE clause when there is

no GROUP BY clause and the HAVING clause does not relate to the aggregate function

used in the SELECT clause.

Implicit Sorts Using DISTINCT

Select Statements that use DISTINCT in Microsoft Access sort by the first SELECT column

if there is no ORDER BY clause. 2SQL will determine the first ordinal positioned column

of the SELECT clause and create an ORDER BY clause to sort on this column.

Implied Boolean Comparisons

WHERE and HAVING clauses that compare boolean expressions are converted to use

CASE. For example:

WHERE A = B = 1

Becomes

WHERE CASE WHEN A = B THEN 1 ELSE 0 END =1





Implied Boolean Expressions

SELECT columns that are implied Booleans are converted to use CASE. For example:

SELECT A = B as C

Becomes

SELECT CASE WHEN A = B THEN 1 ELSE 0 END AS C

Implied Form/Report Control Input Parameters

It is possible in Microsoft Access to refer to a Form or Report control without referring to

the Form or Report name. 2SQL will implement the 2SQL Hosts Utility on such

occurrences. See the category called Implied Input Parameters directly below for more

information.

Implied Input Parameters

Native to JET but foreign to SQL Server, expressions such as

forms!formname!controlname in SQL Statements require posting to SQL Server before

the SQL Statement can be executed. 2SQL replaces Form and Report Control input

parameter references with one of the 2SQL Host Functions. For example:

SELECT * FROM TableName WHERE F1 = forms!formname!controlname

Becomes

SELECT * FROM TableName WHERE F1 =

dbo.Host_VarcharValue(‘Forms_FormName_ControlName’,null)

See the 2SQL Toolkit Document section entitled How and When to Use the 2SQL Hosts

Utility for more information.

Linked SubForms

Forms linked to Subforms via the LinkChild and LinkMaster fields property of the parent

form can suffer significant performance problems once the Access database is upsized to

SQL Server. This is because Microsoft Access will download the entire table/query of the

subform recordsource before it filters out records based on the values of LinkChild. The

2SQL Toolkit has a utility that optimises sub forms. In order for this to work, the SQL

Statement of the subform recordsource must be aware of the current record value of

the LinkMaster property in the parent form. This conversion category covers the

modifications that 2SQL does to the SQL Statement of the recordsource sub form. The

Northwind_CU2 database has an example of this conversion category.





MakeTable Statement Syntax

Computed Columns belonging to the SELECT clause of a MAKETABLE statement that do

not have an Alias will have an Alias created by 2SQL, where the name of the Alias is

“column_” concatenated to the ordinal position value of the computed column.

Memo based DISTINCTs


to fields that were originally of type Memo. The corresponding SQL Server Text field

type cannot be used with DISTINCT. 2SQL will use the CONVERT function as follows:-

SELECT DISTINCT memofield FROM Table1

becomes

SELECT DISTINCT CONVERT(varchar(max),memofield) FROM Table1

Memo Based GROUP BYs

Fields originally of type Memo that reside in the SELECT clause and are used in the

GROUP BY clause of a SQL Statement cannot be grouped because of one of the

restrictions of the SQL Server equivalent field of type Text. SQL will use the CONVERT

function to change these fields to varchar dynamically at run time. For example:-

SELECT T1.MemoVal, SUM(T1.NumVal) FROM T1 GROUP BY T1.MemoVal

Becomes

SELECT CONVERT(varchar(max), T1.MemoVal), SUM(T1.NumVal) FROM T1 GROUP BY

CONVERT(varchar(max),T1MemoVal)

Memo Based Function Parameters

JET accepts fields of type memo as a parameter for string based functions. However, SQL

Server string based functions will not accept fields of type Text as a parameter. 2SQL will

apply a dynamic conversion when Text fields are used in String based SQL Server

functions. For example,

LEFT(textfieldname,10)

Becomes

LEFT(CONVERT(varchar(max),textfieldname),10)





Memo Based Joins

Joins referring to fields originally of type Memo need a dynamic conversion to Varchar

because the SQL Server Text equivalent field type cannot be used with Joins. 2SQL will

implement the CONVERT function to enforce a functional join. For example:

SELECT * FROM Table1INNER JOIN Table2 ON Table1.F1 = Table2.F1

Becomes

SELECT * FROM Table1 INNER JOIN Table2 ON

CONVERT(Varchar(max),Table1.F1)=CONVERT(varchar(max),Table2.F1)

Memo Based ORDER BYs

As per the category directly above applied to the ORDER BY clause, because SQL Server

Text fields cannot be sorted. The SELECT clause is not modified.

Missing Keys in SELECT Clauses

JET does not require all the primary keys of the parent tables of updatable SQL

Statements to reside in the SELECT clause. For example, primary keys of type

AutoNumber are not required. Also, JET will assess the JOIN clauses to see if the column

that is joined to the parent table column is in the SELECT clause. If so, it will use this as

an alias to keep the SQL Statement updatable.

SQL Server however, demands that all keys of all Parent Tables reside in the SELECT

clause, to be updatable. In most instances, 2SQL is able to detect the updatable Parent

Tables of a SQL Statement, and once this has been determined, it will then add the

missing keys to the SELECT clause, allowing the SQL Statement to remain updatable.

This also allows 2SQL to create the corresponding ODBC Indexes, and Triggers if there

are JOINS in the SQL Statements. See the components called ODBC Connection Objects

and SQL Server Objects for more information. 2SQL will also log an alert if it is unable to

identify the Parent Tables of Updatable SQL Statements.

MOD Operators

MOD Operators are replaced with %.

Multiple Object Updates

JET is capable of updating more than one object in the SET clause of UPDATE

statements, but SQL Server is not. 2SQL will generate one UPDATE statement per object

updated, and use the same joins and criteria as the original, per UPDATE statement.





Non Deterministic BETWEEN Clause Comparisons

Non-Deterministic BETWEEN clauses utilize CASE to ensure that the first compare

parameter is less in value than the second. For example:

BETWEEN A AND B

Becomes

BETWEEN CASE WHEN A < B THEN A ELSE B END AND CASE WHEN A < B THEN B ELSE A

END

Non Text Based Concatenations

Concatenation of values that are not of type string/varchar are converted to varchar

before concatenation occurs. For example:

SELECT Integerfield + ‘ ‘ + StringField

Becomes

SELECT Convert(varchar(max),IntegerField) + ‘ ‘ + StringField

When the expression being concatenated is a field of type date, 2SQL will add a style to

the CONVERT function to remove the time component of the expression.

Numeric Alias and Object Names

2SQL will encapsulate Table or Column Alias Names that are Numeric with [].

2SQL will encapsulate Table or Query Object Names that are Numeric with [].





SQL Statements (O to Z)

OLE/HyperLink based DISTINCTs


to fields that were originally of type OLE,HyperLink. These field types cannot be used

with DISTINCT. 2SQL converts such instances as follows:-

OLEField

Convert(varbinary(max),OLEField)HyperlinkField

Convert(varchar(max),HyperLinkField)

OWNERACCESS OPTION

2SQL will remove any OWNERACCESS OPTION clauses in the SQL Statements.





Query Names Longer than 60 Characters in SQL

2SQL will replace references to Query Names longer than 60 characters to the new

Query Name in SQL Statements..

Reserved Key Word Usage

Tables, Queries, Columns and Aliases that are also SQL Server Reserved Key words

circumstantially require encapsulation with []. See the document called 2SQL Reserved

Key Word List for more information.

Rounded Divisions

When the \ Symbol is used to perform divides, 2SQL will round the dividend using

Convert(Integer,...).

SELECTS requiring WITH TIES

SELECT TOP nnn requires WITH TIES in SQL Server to return the same number of rows as

Microsoft Access.

SELECTs with ORDER BY

2SQL will add TOP 9999999 to any SELECT Statement with an ORDER BY clause that is

converted to a SQL Server View, if there is no TOP clause in the original statement.

Square Bracket SELECTs

SELECT Statements that start with [ and end with ] are replaced with round brackets. For

example:

SELECT * FROM [SELECT F1,F2 FROM T1]

Becomes

SELECT * FROM (SELECT F1,F2 FROM T1)

String Concatenation Symbols

The & symbol when used for concatenation of values is replaced with the plus (+)

symbol.

Superfluous DISTINCTs

DISTINCT SELECTS will have DISTINCT removed if all the primary keys of the base/parent

table are used in the SELECT or JOIN sections combined.

Superfluous ORDER BY and GROUP BY expressions

Expressions that are Literal Strings or Numbers as part of ORDER BY or GROUP BY

clauses are removed. This is something that is tolerated by JET but not SQL Server T-SQL,

and has no effect on the result of executing the SQL Statement.





Superfluous Semi Colons

Sub SELECTS in the SQL Statement can end with a semi colon in Microsoft Access. This is

not tolerated in SQL Server so 2SQL removes the semi colon.

TABLE SELECT Clauses

References to the TABLE clause are converted to SELECT. For example:

TABLE TableName

Becomes

SELECT * FROM TableName

TimeStamp Column Exclusion

Using the asterisk (*) to display all columns of a table will now show the newly created

TimeStamp Column called RowVersion (see the category called TimeStamp Columns in

Table Data/Schema section for more information). Timestamp columns should not be

referred to in SQL Statements and will cause the usage of DISTINCT when LEFT OR RIGHT

JOINS are used, to malfunction. 2SQL will replace the asterisk with all the other columns

of the table in the sequence of their ordinal position in the table, thereby removing the

reference to the RowVersion TimeStamp column.

UNIONs with Object Name in ORDER BY Clause

If the ORDER BY clause of the last clause of a UNION statement refers to

ObjectName.ColumnName syntax then the UNION statement itself is converted to a

Table Alias and the ObjectName is removed from the ORDER BY Clause. For example:

SELECT F1,F2 FROM T1 UNION SELECT F1,F2 FROM T2 ORDER BY T2.F2

Becomes

SELECT TOP 9999999 * FROM (SELECT F1,F2 FROM T1 UNION SELECT F1,F2 FROM T2 )

ORDER BY F2

UNIONs with Superfluous ORDER BY Clause

The ORDER BY clauses of a UNIION statement are removed if they do NOT belong to the

LAST UNION clause. Such instances are superfluous in JET and not tolerated by SQL

Server T-SQL.





UPDATE Statement Syntax

If the SET clause of an UPDATE clause occurs AFTER the FROM clause, it is moved to

occur directly BEFORE the FROM clause.

UPDATE Statements that refer to JOINS without a FROM clause are modified to refer to

the table/view being updated directly after the UPDATE clause, followed by a FROM

clause that refers to both the table/view being updated, and the corresponding JOINS.

The DISTINCTROW and DISTINCT clauses are removed from UPDATE clauses.

User Defined Input Parameters

Input Parameters of SQL Statements are replaced with one of the 2SQL HOSTS utility

functions. For example:

SELECT * FROM TableName WHERE F1 = [Enter Product Code]

Becomes

SELECT * FROM TableName WHERE F1 =

dbo.Host_VarcharValue(‘Enter_Product_Code’,’’)

See the 2SQL Toolkit Document section entitled How and When to Use the 2SQL Hosts

Utility for more information.

Wildcard References

The Ansi89 Wildcard Symbols Exclamation Mark, Asterisk, and Question Mark are

converted to Caret, Percentage sign, and Underscore respectively. References to LIKE

are replaced with an equal (=) symbol if there are no Wildcards referred to. References

to NOT LIKE are replaced with <> if there are no Wildcards referred to.

XOR Operator

2SQL will replace the XOR operator with the built in 2SQL Toolkit Function called

XOR2SQL.





VBA Functions (A to D)

ASC Function

2SQL will replace the ASC Function with ASCII. Includes ASC% usage.

CCUR Function

2SQL will replace the CCUR Function with CONVERT(Money, - Includes CCUR% usage

CDATE Function

2SQL will replace the CDATE Function with CONVERT(smalldatetime.

CDBL Function

2SQL will replace the CDBL Function with CONVERT(float. – Includes CDBL% usage





CHOOSE Function

2SQL will replace the CHOOSE Function with CASE. For example,

CHOOSE(indexfield,field1,field2)

becomes

CASE WHEN indexfield = 1 THEN Field1 WHEN indexfield = 2 THEN field2 ELSE NULL END

CHR Function

2SQL will replace the CHR Function with CHAR. Includes CHR$ usage.

CINT Function

2SQL will replace the CINT Function with CONVERT(smallint, - Includes CINT% usage.

CLNG Function

2SQL will replace the CLNG Function with CONVERT(integer, - Includes CLNG% usage.

CSNG Function

2SQL will replace the CSNG Function with CONVERT(real,

CSTR Function

2SQL will replace the CSTR Function with CONVERT(varchar(max), - Includes CSTR$

usage.

CURRENTUSER Function

2SQL will replace the CURRENTUSER Function with the SQL Server Function called

HOST_NAME(). The CURRENTUSER Function in Microsoft Access is obsolete as of Access

2010 because it is part of the deprecated Workgroup Security Module in Microsoft

Access. The HOST_NAME() function in SQL Server is its closest equivalent but services

may be required post conversion to ensure desired outcome.

CVDATE Function

2SQL will replace the CVDATE Function with CONVERT(datetime, - Includes CVDATE%

usage.

DATE Function

2SQL will replace the DATE Function with GETDATE().

DATEADD Function

2SQL will replace the first parameter of the DATEADD Function with its SQL Server

Equivalent. For example, DATEADD(“dd” is replaced with DATEADD(d

DATEDIFF Function

2SQL will replace the first parameter of the DATEDIFF Function with its SQL Server

Equivalent. For example, DATEDIFF(“dd” is replaced with DATEDIFF(d





DATEPART Function

2SQL will replace the first parameter of the DATEPART Function with its SQL Server

Equivalent. For example, DATEPART(“dd” is replaced with DATEPART(d

DATESERIAL Function

2SQL will replace the DATESERIAL Function with its own 2SQL Toolkit Function

DATESERIAL2SQL. The 2SQL Toolkit is provided with every 2SQL Conversion project.

DATEVALUE Function

2SQL will replace the DATEVALUE Function with CONVERT(varchar(max), with a style

value of 110

DAVG Function

2SQL will replace the DAVG Function with an equivalent domain SELECT clause. For

example,

DAVG(domain,column,criteria)

Becomes

(SELECT AVG(column) FROM domain WHERE criteria)

DAY Function

2SQL will replace the DAY Function with DATEPART(d – Includes DAY% usage.

DCOUNT Function

2SQL will replace the DCOUNT Function with an equivalent domain SELECT clause. For

example,

DCOUNT(domain,column,criteria)

Becomes

(SELECT COUNT(column) FROM domain WHERE criteria)

DLOOKUP Function

2SQL will replace the DLOOKUP Function with an equivalent domain SELECT clause. For

example,

DLOOKUP(domain,column,criteria)

Becomes

(SELECT TOP 1 column FROM domain WHERE criteria)

DMAX Function

2SQL will replace the DMAX Function with an equivalent domain SELECT clause. For

example,

DMAX(domain,column,criteria)

Becomes





(SELECT MAX(column) FROM domain WHERE criteria)

DMIN Function

2SQL will replace the DMIN Function with an equivalent domain SELECT clause. For

example,

DMIN(domain,column,criteria)

Becomes

(SELECT MIN(column) FROM domain WHERE criteria)

DSUM Function

2SQL will replace the DSUM Function with an equivalent domain SELECT clause. For

example,

DSUM(domain,column,criteria)

Becomes

(SELECT SUM(column) FROM domain WHERE criteria)





VBA Functions (E to M)

FIRST Function

2SQL will replace the FIRST Function with a SELECT TOP 1 ...FROM Criteria ORDER BY

expression based on the characteristics of the column and table that the function is

being used for.

FIX Function

2SQL will replace the FIX Function with ROUND(nnn,0,1).

FORMAT Function

2SQL will replace the FORMAT Function with an equivalent CONVERT function or other

SQL Server Functions depending on the Format parameter. For example

Format(xxx,”dd/mm/yyyy”)

Becomes

CONVERT(VARCHAR(max), xxx, 103)

Includes FORMAT$ usage.





FORMATCURRENCY Function

2SQL will replace the FORMATCURRENCY Function with its own 2SQL Toolkit Function

FORMATCURRENCY2SQL. The 2SQL Toolkit is provided with every 2SQL Conversion

project.

FORMATDATETIME Function

The FORMATDATETIME function in Microsoft Access is an alternative to the FORMAT

function in Microsoft Access. 2SQL will calculate the equivalent FORMAT expression and

replace the FORMATDATETIME function with its FORMAT function equivalent and apply

the same rules as when converting the FORMAT function. See the FORMAT Function

category in this document for more information.

FORMATNUMBER Function

2SQL will replace the FORMATNUMBER Function with its own 2SQL Toolkit Function

FORMATNUMBER2SQL. The 2SQL Toolkit is provided with every 2SQL Conversion

project.

FV Function

2SQL will replace the FV Function with its own 2SQL Toolkit Function FV2SQL. The 2SQL

Toolkit is provided with every 2SQL Conversion project.

HOUR Function

2SQL will replace the HOUR Function with DATEPART(hh – Includes HOUR% usage.

IIF Function

2SQL will replace the IIF Function with CASE. For example,

IIF(a=b,c,d)

Becomes

CASE WHEN a=b THEN c ELSE d END

INSTR Function

2SQL will replace the INSTR Function with CHARINDEX with parameters reordered.

INSTRREV Function

2SQL will replace the INSTR Function with its own 2SQL Toolkit Function INSTRREV2SQL.

The 2SQL Toolkit is provided with every 2SQL Conversion project.

INT Function

2SQL will replace the INT Function with CONVERT(integer,

IPMT Function

2SQL will replace the IPMT Function with the 2SQL Toolkit Function IPMT2SQL. The 2SQL






ISNULL Function

2SQL will replace the ISNULL Function with the following depending on how it is used.

For example,

ISNULL(a)

Becomes

CASE WHEN a IS NULL THEN ELSE 0 END

Or

a IS NULL

Or

a IS NOT NULL

LAST Function

2SQL will replace the LAST Function with a SELECT TOP 1 ...FROM Criteria ORDER

BY..DESC expression based on the characteristics of the column and table that the

function is being used for.

LCASE Function

2SQL will replace the LCASE Function with LOWER. Includes LCASE$ usage.

LEFT Function

2SQL will replace the LEFT Function with LEFT when it is expressed as LEFT$.

LEN Function

2SQL will replace the LEN Function with DATALENGTH. Includes LEN% usage.

LTRIM Function

2SQL will replace the LTRIM Function with LTRIM when it is expressed as LTRIM$.

MID Function

2SQL will replace the MID Function with SUBSTRING and resequence the parameters.

Includes MID$ and MID% usage.

MINUTE Function

2SQL will replace the MINUTE Function with DATEPART(mi, - Includes MINUTE% usage.

MONTH Function

2SQL will replace the MONTH Function with DATEPART(mm, - Includes MONTH% usage.





VBA Functions (N to Z)

NOW Function

2SQL will replace the NOW Function with GETDATE()

NZ Function

2SQL will replace the NZ Function with ISNULL and an extra parameter if required. For

example,

NZ(stringvalue)

Becomes

ISNULL(stringvalue,’’)





PARTITION Function

2SQL will replace the PARTITION Function with its own 2SQL Toolkit Function

GETPARTITIONRANGES2SQL. The 2SQL Toolkit is provided with every 2SQL Conversion

project.

PMT Function

2SQL will replace the PMT Function with its own 2SQL Toolkit Function PMT2SQL. The

2SQL Toolkit is provided with every 2SQL Conversion project.

PPMT Function

2SQL will replace the PPMT Function with its own 2SQL Toolkit Function PPMT2SQL. The


PV Function

2SQL will replace the PV Function with its own 2SQL Toolkit Function PV2SQL. The 2SQL


RIGHT Function

2SQL will replace the RIGHT Function with RIGHT when it is expressed as RIGHT$.

ROUND Function

2SQL will add a second parameter with a value of zero (0) to the ROUND function if

there is only one parameter referred to in this function.

RND Function

2SQL will replace the RND Function with the SQL Server RAND function.

RTRIM Function

2SQL will replace the RTRIM Function with RTRIM when it is expressed as RTRIM$.

SPACE Function

2SQL will replace the SPACE Function with SPACE when it is expressed as SPACE$

STR Function

2SQL will replace the STR Function with STR when it is expressed as STR$

STRCONV Function

2SQL will replace the STRCONV Function with the 2SQL Toolkit Function STRCONV2SQL.

The 2SQL Toolkit is provided with every 2SQL Conversion Project.

STRING Function

2SQL will replace the STRING Function with REPLICATE

STRREVERSE Function

2SQL will replace the STRREVERSE Function with REVERSE.





TIME Function

2SQL will replace the TIME Function with GETDATE() when used for Default Value

Constraints.

TRIM Function

2SQL will replace the TRIM Function with LTRIM(RTRIM – Includes TRIM$ usage.

UCASE Function

2SQL will replace the UCASE Function with UPPER. Includes UCASE$ usage.

User Defined Function References

References to Custom VBA Functions are converted to refer to their SQL Server User

Defined Function Template Equivalent expression. For example:-

SELECT CustomFunction(xxx)

Becomes

SELECT dbo.CustomFunction(xxx)

See the category called User Defined Function Templates for more information.

VAL Function

2SQL will replace the VAL Function with its own 2SQL Toolkit Function VAL2SQL. The


WEEKDAY Function

2SQL will replace the WEEKDAY Function with DATEPART(dw, - Includes WEEKDAY%

usage.

YEAR Function

2SQL will replace the YEAR Function with DATEPART(yy – Includes YEAR% usage.





SQL Server Objects

Table Creation

For every Table in the original Microsoft Access Database, 2SQL will create the

corresponding SQL Server Table.

Append Stored Procs

2SQL Converts Access Append Queries to SQL Server Stored Procedures.

Update Stored Procs

2SQL Converts Access Update Queries to SQL Server Stored Procedures.

Delete Stored Procs

2SQL Converts Access Delete Queries to SQL Server Stored Procedures.

MakeTable Procs

2SQL Converts Access MakeTable Queries to SQL Server Stored Procedures.





CrossTab Procs

2SQL Converts Access CrossTab Queries that do not have an IN Clause to SQL Server

Stored Procedures.

Select and Union Views

2SQL Converts Access Select and Union Queries to SQL Server Views.

CrossTab Views

2SQL Converts Access CrossTab Queries that have an IN Clause to SQL Server Views.

User Defined Function Templates

For each Custom VBA Function used in the SQL Statements, a SQL Server User Defined

Function Template is created by 2SQL for the Conversion programmer to continue on

converting the VBA coding to T-SQL. This encompasses the function parameters and

their data types, as well as returning the corresponding SQL Server data type. For

example, a Custom VBA Function that returns a String, will be converted to return

Varchar(max) in SQL Server. The original VBA code of the Custom VBA Function is also

migrated to SQL Server, but in a commented state so as to assist in the manual

conversion of this code to T-SQL Syntax.

UPDATE Triggers for Tables

When the creation of Foreign Key Constraints by 2SQL fails with an error message

advising of cycle or multiple cascade paths, or the source table needs an INSTEAD OF

UPDATE Trigger, 2SQL create an UPDATE trigger on the source table. These Update

triggers serve to provide the same functionality as the original table relationship when

updating records of the source table.

DELETE Triggers for Tables


advising of cycle or multiple cascade paths, or the source table needs an INSTEAD OF

DELETE Trigger, 2SQL will create a DELETE trigger on the source table. These Delete

triggers serve to provide the same functionality as the original table relationship when

deleting records from the source table.

INSERT Triggers for Tables


advising of cycle or multiple cascade paths, or the foreign table needs an INSTEAD OF

INSERT Trigger, 2SQL create an INSERT trigger on the foreign table. These Insert triggers

serve to provide the same functionality as the original table relationship when inserting

records into the foreign table.





INSTEAD OF INSERT Triggers for Tables

Insertion of rows to a table with fields of type Boolean that originally allowed null values

require an INSTEAD OF INSERT trigger. This is because Access dynamically converts null

value Boolean fields to False before it writes to the table. However, this functionality is

lost when the table is linked to SQL Server. 2SQL will create an INSTEAD OF INSERT

trigger on all tables that have this criteria, and implement the ISNULL function to write a

value of 0 to the corresponding fields of type Bit in SQL Server. See the category called

Nullable Boolean Fields in the Table Schema/Data section for more information.

INSTEAD OF DELETE Triggers for Views

SQL Statements with JOINS that are converted to Updateable Views cannot have rows

deleted without an INSTEAD OF DELETE Trigger in SQL Server. 2SQL will calculate the

primary table and unique columns of each View, and create the trigger.

INSTEAD OF UPDATE Triggers for Views


updated without an INSTEAD OF UPDATE Trigger in SQL Server. 2SQL will calculate

which tables can be updated and create the trigger.

INSTEAD OF INSERT Triggers for Views


inserted without an INSTEAD OF INSERT Trigger in SQL Server. 2SQL will calculate the

primary table and unique columns of each View, and create the trigger. Other tables in

the view that are updatable will have their own UPDATE commands as part of the

trigger.

Foreign Key Constraints

2SQL will create a SQL Server Foreign Key Constraint for each Table Relationship in

Microsoft Access Rule. Columns belonging to Table Relationships will be set not to allow

null values irrespective of the value of the Required Property of the table column, so

long as the data in the table does not conflict with this condition.

Check Constraints

2SQL will create a SQL Server CHECK Constraint for each Column Validation Rule.

Default Value Constraints

2SQL will create a SQL Server Default Constraint for each Column Default Value.

Virtual Table RowCount Reconciliation

For every SQL Statement in the Access Queries, RecordSource of Forms and Reports, and

RowSource property of Forms and Reports, 2SQL will execute the Statement in Access

and Log the number of rows it returns.

When 2SQL creates the corresponding SQL Server View or Stored Procedure, it executes

once more and compares the row count. If the original row count is greater than zero,

and the SQL Server Row Count matches, this is logged as a successful virtual rowcount

reconciliation. If there is a row count conflict, an error is logged for review post

conversion.





ODBC Connection Objects

ODBC Links to Tables

2SQL will delete the original Table object in the Access Database and replace it with an

ODBC Linked object connected to the equivalent SQL Server Table.

ODBC Links to Views

For SQL Statements that have been converted to SQL Server Views, 2SQL will delete the

original object in the Access Database and replace it with an ODBC Linked object

connected to the equivalent SQL Server View.

ODBC Indexes

SQL Statements that are converted to Updateable Views are not updateable from the

Microsoft Access Front End without a dummy “pseudo index” applied to the

corresponding linked object. 2SQL will calculate the primary table and unique columns

of each View, and create the pseudo index using the DAO Create Index command. This

is a particularly complex operation to perform when the SQL Server View refers to

multiple tables via JOINS.

Pass-Through Queries

For SQL Statements that have been converted to SQL Server Stored Procedures, 2SQL

will delete the original object in the Access Database and replace it with an ODBC Pass-

Through linked object connected to the equivalent SQL Server Stored Procedure.





Application Framework

Aggregate Functions in Form Controls

2SQL will replaces references to the SUM Function in Form controls with the built in

2SQL Toolkit Function DSUMDIRECT. Otherwise SUM functions in Form Controls can

severely compromise performance due to Microsoft Access downloading the entire

recordsource before applying the computation of this function.

Form/Report ControlSource Syntax

The ControlSource property of Form and Report Controls may be bound to a column of

the recordsource that originally contained a full stop due to the way JET handles

duplicate column names. 2SQL will replace the ControlSource value with its converted

SQL Server equivalent name. For example,

QueryName.FieldName

Becomes

QueryName_FieldName

See the conversion category called Duplicate Column Aliases in the SQL Statements

component for more information.





ControlSource Syntax of Report GroupLevels

Same as the category directly above but applied to the ControlSource property of the

GroupLevel objects in Reports.

Form/Report ORDER BY Properties

The OrderBy property of a Form will enforce client side processing when these objects

load, if the OrderByOnLoad property is set to true. The syntax of the OrderBy property

can also be incorrect because the RecordSource property may refer to a newly created

SQL Server View as a result of the 2SQL Conversion process. 2SQL will automatically

transfer the value of the OrderBy property to the View that the RecordSource property

refers to. If this view was originally an Access query, 2SQL will create a new View with an

ORDER BY clause, derived from the original Access Query. Otherwise it will remove the

original ORDER BY clause of the View that 2SQL created, and replace it with the OrderBy

property of the form. This ensures server side processing when Forms are loaded.

This category also applies to Reports.

Form/Report RecordSource Properties

2SQL will convert SQL Statements that reside in the RecordSource property of Forms to

SQL Server Views or Stored Procedures. 2SQL will then set the RecordSource property to

the name of the new SQL Server object. Views created from the RecordSource property

have a naming convention of ObjectName_RS


Form/Report RowSource Properties

2SQL will convert SQL Statements that reside in the RowSource property of Form

controls to SQL Server Views or Stored Procedures. 2SQL will then set the RowSource

property to the name of the new SQL Server object. Views created from the RowSource

property have a naming convention of ObjectName_ControlName_Rows.






Form/Report ControlSource Properties with Input Parameters

The ControlSource property of Form controls can refer to input parameters of the SQL

Statement of the RecordSource. User defined input parameters no longer exist in the

front end due to the SQL Statement now residing in SQL Server as a View or Stored

Procedure, and 2SQL has already replicated this functionality by implementing the 2SQL

Hosts Utility. See the category called User Defined Input Parameters in the SQL

Statements component for more information. 2SQL will replace any reference to a user

defined input parameter with its corresponding VBA Function in the 2SQL Module. See

the section entitled All about the other 2SQL Functions in the 2SQL Toolkit Document for

more information. For example:-

[Enter Beginning Date]

Becomes

DateTimeValue(“Enter Beginning Date”)


Query Names Longer than 60 Characters

The SQL Server Native Client Driver does not allow ODBC connections to have object

names greater than 60 characters. 2SQL will truncate Query Object Names to the first

available name less than or equal to 60 characters. See the related category in the SQL

Statements section of this document.

Query Metadata

2SQL will migrate Microsoft Access Query Description values to SQL Server as a SQL

Server property in the corresponding View or Stored Procedure.

Table Metadata

2SQL will migrate Microsoft Access Table and Field Description values to SQL Server as a

SQL Server property in the corresponding Table or Field.

Updatable Forms with Read Only Recordsets

Forms with read only recordsets, but with the AllowAdditions, or AllowDeletions

properties set to true will be changed to false by 2SQL. This is done to assist in the

reconciliation process post conversion, during the cleanup phase. See the 2SQL

Preparation and Cleanup guide for more information. The AllowEdits property is left

alone due to the possibility of having controls that are not bound to the recordset.

If 2SQL cannot determine with certainty on whether or not the recordset is read only, it

will log an error of type Alert, for manual review.





Parent Table Key Changes from Forms

Forms of view type datasheet with form controls that have controlsources bound to the

primary keys of any of the parent tables of an updateable recordset, require a form

refresh command in the afterupdate event when an existing record is being modified.

Changing the value of a primary key is the same as deleting the existing record and

inserting a new one. A #deleted# error message will display unless the form is refreshed.

If there is no afterupdate event, 2SQL will create the VBA Event Procedure. If the

afterupdate event refers to another macro, 2SQL will change it to [Event Procedure] and

create the VBA AfterUpdate event. This event will perform a docmd.RunMacro to run

the original macro. The event procedure will also do a me.refresh and a

me.recordset.findfirst to reset the bookmark of the recordset, if me.newrecord returns

false.

Child Table Key Changes from Forms

Form controls with controlsources that are bound to columns of child table(s) of an

updateable recordset by way of a join to a column of any of the parent tables that are

NOT a primary key, require a form refresh command in the afterupdate event.

Dependant data on the form that belongs to the child table will not display in the form

unless a form refresh occurs. In such instances 2SQL will modify the afterupdate event

of the appropriate form controls to execute a form refresh. If there is no afterupdate

event, 2SQL will modify the afterupdate property to call the built in 2SQL Macro called

RefreshForm. If the afterupdate event refers to another macro, 2SQL will change it to

[Event Procedure] and create the VBA AfterUpdate event that does a me.refresh and

then does a docmd.RunMacro of the original macro. If the afterupdate event already

referred to [Event Procedure] then 2SQL will add a me.refresh to the event.

Form Controls bound to Tables with Default Values

Form controls with a controlsources that are bound to columns of a table either directly

or by way of a query can have default values. If such cases, the Access Form engine will

propagate the default value into the form control at run time. However, Access will not

do this for tables linked to SQL Server because the default value is now a constraint in

SQL Server. When the DefaultValue property of a form control is null, 2SQL will set this

property to the original default value of the table that the form control is bound to. This

change provides identical functionality when the tables are linked to SQL Server.

2SQL Toolkit Objects

2SQL will create various tables, views, stored procedures and user defined functions that

form part of the 2SQL Toolkit, during the conversion process. These objects are needed

to provide the same functionality of the original application. For more information, see

the section about the 2SQL Toolkit in the 2SQL Toolkit Document.





Optimization of Data Objects

Domain Functions

Domain Functions are converted to their equivalent 2SQL Toolkit function.

For example, DLOOKUP is converted to DLOOKUPDirect.

2SQL converts Domain Functions in both VBA Code references, and also the

controlsource property of Forms and Reports.

For more information, see the section entitled How and When to Implement the 2SQL

ExecuteScalar Utility in the 2SQL Toolkit Document, and the module called 2SQL that is

created by 2SQL for every Access database processed in Genie Mode, for more

information.

RunSQL Usage

2SQL will convert all DoCmd.RunSQL references to the ADO/OLE equivalent using the

2SQL ExecuteSQLCommand Function. For example:-

DoCmd.RunSQL SQLStatement

Becomes

ExecuteSQLCommand SQLStatement,ADODirectConnection





See the 2SQL Toolkit Document section about the 2SQL Connection Settings Utility and

the 2SQL Functions for more information.





Code Alerts

When 2SQL analyses the VBA code, it will enforce compilation errors for lines of code

that require manual intervention to complete the optimization or conversion process.

For example, if an SQL Statement is used in an OpenRecordSet command as opposed to

the name of a Table, 2SQL will generate a code alert so that the code will no longer

compile until the SQL Statement is manually reviewed, remedied, and recompiled.

DAO RecordSet Variable Declarations

2SQL will convert DAO RecordSet Declarations to ADODB Recordset Declarations. For

example:-

Dim rst as DAO.RecordSet

Becomes

Dim rst as ADODB.RecordSet

DAO RecordSet Instantiations

2SQL will convert all OpenRecordSet references to the ADO equivalent using the 2SQL

ADODirectConnection Function. For example:-

Set RST = CurrentDB.OpenRecordSet(SQLStatement,dbOpenDynaset)

Becomes

Set RST = New ADODB.RecordSet

RST.Open SQLStatement,ADODirectConnection,adOpenKeyset

See 2SQL Toolkit Document section about the 2SQL Connection Settings Utility for more

information.





DAO RecordSet Properties

When converting DAO Recordsets to ADO, 2SQL also converts the recordset properties

as follows:

DAO RecordSet Property ADO RecordSet Property

Batchsize Removed

Bookmarkable Supports(adBookMark)

CacheStart Removed

Connection ActiveConnection

Edit Removed

FillCache Removed

FindFirst Combination of MoveFirst,Find and EOF

FindLast Combination of MoveLast,Find and BOF

FindNext Find with AdSearchForward

FindPrevious Find with adSearchBackward

LastModified Removed

LockEdits Combination of LockType,ADODB.LockType enum

NoMatch EOF, BOF

PercentPosition AbsolutePosition*100/RecordCount

RecordStatus Status

Requery ActiveCommand

Seek Combination of adSeekEnum

StillExecuting State=adStateExecuting

Updateable Supports(adUpdate)





DAO Executes

2SQL will convert all DAO Execute references to the ADO equivalent using the 2SQL

ExecuteSQLCommand Function. For example:-

CurrentDB.Execute SQLStatement

Becomes

ExecuteSQLCommand SQLStatement,ADODirectConnection

See the 2SQL Toolkit Document section about the 2SQL Connection Settings Utility and

2SQL Functions for more information.

DAO DBEngine Commands

2SQL will convert the DAO DBEngine Transaction commands to use the 2SQL

ADODirectConnection function. For example:-

DBEngine.BeginTrans

Becomes

ADODirectConnection.BeginTrans

See the 2SQL Toolkit Document section about the 2SQL Connection Settings Utility for

more information.

ADO RecordSet Instantiations

2SQL will convert all ADO Recordset instantiations to use the 2SQL Toolkit function

called CachedADORecordset. This function allows the setting of the cachesize property

of an ADO Recordset, which can prove very beneficial for performance on large tables.

See the 2SQL Toolkit Document for more information.

Obsolete DAO Usage

2SQL will convert WorkSpaces(0).Databases(0) to CurrentDB()

CurrentProject Connections

2SQL will replace all references to the JET based CurrentProject.Connection property

with the built in

OLE based 2SQL Toolkit Function called ADODirectConnection. See 2SQL Toolkit

Document section about the 2SQL Connection Settings Utility for more information.





VBA Framework

CloseQuery Calls

2SQL will replace all references to DoCmd..Close acQuery with the built in 2SQL Toolkit

function called CloseQuery2SQL. This function checks if the original query object is now

a linked table referring to a SQL Server view. If so, acQuery is replaced with acTable.

OpenQuery Calls

2SQL will replace all references to DoCmd.OpenQuery with the built in 2SQL Toolkit

function called OpenQuery2SQL. This function checks if the original query object is now

a linked table referring to a SQL Server view. If so, OpenQuery is replaced with

OpenTable. It will also call the built in 2SQL Toolkit function called

CheckQueryInputParameters. See the category called OpenQuery SetHostValue Calls for

more information.

OpenForm Calls

2SQL will replace all references to DoCmd.OpenForm with the built in 2SQL Toolkit

function called OpenForm2SQL. This function calls the built in 2SQL Toolkit function

called CheckFormInputParameters. See the category called OpenForm SetHostValue

Calls for more information.

OpenReport Calls

Same as category directly above applied to Reports.





OpenQuery SetHostValue Calls

Query objects executed via DoCmd.OpenQuery may originally have had input

parameters. The values of these input parameters require posting to SQL Server via the

built in 2SQL Toolkit function called SetHostValue. 2SQL will propagate the built in

function called CheckQueryInputParameters with all the necessary calls to SetHostValue.

CheckQueryInputParameters is called from the built in 2SQL Toolkit function called

OpenQuery2SQL. See the category called OpenQuery Calls and the section called How

and When to implement to 2SQL Hosts Utility in the 2SQL Toolkit Document for more

information.

OpenForm SetHostValue Calls

The recordsource property of a form may originally have had input parameters. The

values of these input parameters require posting to SQL Server via the built in 2SQL

Toolkit function called SetHostValue. 2SQL will propagate the built in function called

CheckFormInputParameters with all the necessary calls to SetHostValue.

CheckFormInputParameters is called from the built in 2SQL Toolkit function called

OpenForm2SQL. See the category called OpenForm Calls and the section called How and

When to implement to 2SQL Hosts Utility in the 2SQL Toolkit Document for more

information.

OpenReport SetHostValue Calls

Same as category directly above applied to Reports.

Queries Longer than 60 Characters in VBA Code

2SQL will replace references to Query Names longer than 60 characters in the VBA code

with the new Query Name. See related categories for 60 character limits in other

sections of this document.





Deploy to Production Environment

Recreate Table Objects and Data

2SQL will recreate all Table Schema, Data, Table Triggers and Constraints from the latest

production copy of the Microsoft Access database.

New Table Objects

Any tables in the SQL Server source back end database that are not in the Destination

database are copied across from source to destination.

HostName Tables

Tables that had the HostName column added to it during the cleanup phase of the

conversion project are detected and transferred to the destination tables. See the 2SQL

Toolkit Document section about the 2SQL Hosts Utility for more information.

User Defined Functions

2SQL will copy all User Defined Functions in the SQL Server Source back end database to

the SQL Server destination database.

Views

2SQL will copy all Views in the SQL Server Source back end database to the SQL Server

destination database.

View Triggers

2SQL will copy the Triggers of all Views in the SQL Server Source back end database to






Stored Procedures

2SQL will copy all the Stored Procedures in the SQL Server Source back end database to


Pseudo Index Table Data

2SQL will migrate the data of the tblPseudo_Indexes table across to the destination

database. See the category called ODBC Indexes in the ODBC Connection objects for

more information.

____________________________





2SQL Version History

Version Number Major Revision Initiative

Version 3.0 Used Upsizing Wizard to create ADP front end and continued on

from where Wizard left off. SQL Server 2005/Access 2003

solution - October 2005.

Version 4.0 Completely independent of Upsizing Wizard and SSMA to provide

Server Side processing linked table solution - November 2007.

Version 4.1 SQL Server 2008/Access 2007 installer added - September 2009.

Version 4.2 Upgraded to .NET 3.5 Framework from 2.0 – January 2010.

Version 4.3 Windows 7.0 compatible – March 2010.

Version 4.4 Deploy to Production Environment conversion component

introduced– May 2010.

Version 4.5 Rollback option to migrate data from SQL Server to Microsoft

Access if problems encountered after Deploy to Production

Environment are insurmountable - August 2010.

Version 4.6 2SQL Inspector released. This utility allows users to scan their

entire network drives for Access Databases and log statistical

information to a SQL Server database repository from which

reports can be written to scope the magnitude and complexity of

Access to SQL Server projects – October 2010.

Version 4.7 Conversion Elements introduced to the 2SQL Business Model in

order to provide more flexibility to user when using built in

formulae to calculate the number of hours that 2SQL eliminates

for a conversion project. Expansion of warranty to all conversion

categories, including those that are common to Microsoft's

Upsizing Wizard and SSMA tools – December 2010.

Version 5.0 SQL Azure Ready – January 2011.

Version 5.1 SQL Server 2008/Access 2010 installer added – January 2011.

Version 5.2 Command Line options enabling 2SQL to process databases

without any user interaction – March 2011.

Version 5.3 A small number of Conversion Categories made applicable or

inapplicable depending on the version of Microsoft Access –

February 2013.





Version 5.4 2SQL Inspector renamed to MSO Inspector and provided as a

module of 2SQL – January 2014.

Disclaimer

The Access to SQL conversion and migration challenge is a very complex subject. Whilst

every effort has been made to completely and accurately represent the conversion

issues and their corresponding solution, we do not claim perfection in our analysis. For

that reason we welcome reader feedback to [email protected] as part of our

commitment to continue to keep 2SQL the best product of its type on the world market

today.

____________________________



mailto:[email protected]