2 copyright © 2004, oracle. all rights reserved. using globalization support

2Copyright © 2004, Oracle. All rights reserved.

Using Globalization Support

2-2 Copyright © 2004, Oracle. All rights reserved.

Objectives

After completing this lesson, you should be able to:

• Customize language-dependent behavior for the database and individual sessions

• Specify different linguistic sorts for queries

• Retrieve data that matches a search string ignoring case or accent differences

• Obtain Globalization support configuration information


Globalization Support Features

• Language support

• Territory support

• Character set support

• Linguistic sorting

• Message support

• Date and time formats

• Numeric formats

• Monetary formats


Encoding Schemes

Oracle Database supports different classes of character encoding schemes:

• Single-byte character sets– 7-bit– 8-bit

• Fixed-width multibyte character sets

• Varying-width multibyte character sets

• Universal character sets, such as Unicode


Database Character Sets and National Character Sets

Can store Unicode using either AL16UTF16 or UTF8

Can store varying-width character sets

Store data columns of type NCHAR, NVARCHAR2, NCLOB

Store data columns of type CHAR, VARCHAR2, CLOB, LONG

Can be exchangedCannot be changed without re-creation, few exceptions

Defined at creation timeDefined at creation time

National Character SetsDatabase Character Sets


Datetimes with Timezones

TIMESTAMP '2004-01-31 09:26:56.66 +02:00'

Valid value in V$TIMEZONE_NAMESTIMEZONE_REGION

00 to 59TIMEZONE_MINUTE

-12 to 14TIMEZONE_HOUR

00 to 59.9 (N) -- N indicates precisionSECOND

00 to 59MINUTE

00 to 23HOUR

01 to 31DAY

01 to 12MONTH

-4712 to 9999 (excluding 0)YEAR

Valid ValuesDatetime Field


Configuring the Database Local Timezone

• At the session level:

• Using an environment variable:

• At the database level:

ALTER SESSION SET time_zone = 'Europe/London';

ALTER SESSION SET time_zone = LOCAL;

$ export ORA_SDTZ = 'DB_TZ'

CREATE DATABASE ...

SET TIME_ZONE='UTC' ...

ALTER DATABASE SET TIME_ZONE='-01:00';


Configuring Datetime Formats

• NLS_TIMESTAMP_FORMAT• NLS_TIMESTAMP_TZ_FORMAT

Timezone Daylight savings timeTZD

Timezone region nameTZR

Timezone minutesTZM

Timezone hourTZH

Fractional secondsFF

DefinitionFormat Element

ALTER SESSION SET NLS_TIMESTAMP_TZ_FORMAT =

'YYYY-MM-DD HH:MI:SS.FF TZR TZD';


Using Timezones

01-31-04 09:30:00.00 -05:00

01-31-04 09:30:00.00 America/New_York

01-31-04 13:30:00.00 -01:00

CREATE TABLE orders ( ...orderdate2 TIMESTAMP(3) WITH TIME ZONE ...);

INSERT INTO orders VALUES (...,'28-OCT-04 11:24:54.000 PM America/New_York', ...);


SELECT sysdate FROM dual;

Initialization parameter

Environment variable

ALTER SESSION command

Specifying Language-Dependent Behavior

SQL function


Specifying Language-Dependent Behavior for the Server

• NLS_LANGUAGE specifies:– The language for database messages– Day and month names– Symbols for A.D., B.C., a.m., p.m.– The default sorting mechanism– Affirmative and negative response strings

• NLS_TERRITORY specifies:– Day and week numbering– Credit and debit symbols– Default date format, decimal character,

group separator, list separator and the default ISO, dual and local currency symbols


Language and Territory Dependent Parameters

Parameter

NLS_LANGUAGE NLS_DATE_LANGUAGE NLS_SORT

Default Values

AMERICAN AMERICAN BINARY

AMERICA $ $ AMERICA DD-MON-RR ., DD-MON-RRHH.MI.SSXFF AM DD-MON-RRHH.MI.SSXFF AM TZR

NLS_TERRITORY NLS_CURRENCY NLS_DUAL_CURRENCY NLS_ISO_CURRENCY NLS_DATE_FORMAT NLS_NUMERIC_CHARACTERS NLS_TIMESTAMP_FORMAT NLS_TIMESTAMP_TZ_FORMAT


Other NLS Server Parameters

Parameter Default Value

NLS_CALENDAR Gregorian

NLS_COMP BINARY

NLS_LENGTH_SEMANTICS BYTE

NLS_NCHAR_CONV_EXCP FALSE


Specifying Language-Dependent Behavior for the Session

• Specify the locale behavior with the NLS_LANG environment variable:– Language– Territory– Character set

• Set other NLS environment variables to:– Override database initialization parameter settings

for all sessions– Customize the locale behavior– Change the default location of the NLS library files

NLS_LANG=FRENCH_CANADA.WE8ISO8859P1


ALTER SESSION SET NLS_DATE_FORMAT='DD.MM.YYYY';

DBMS_SESSION.SET_NLS('NLS_DATE_FORMAT','''DD.MM.YYYY''') ;

Specifying Language-Dependent Behavior for the Session


Locale Variants

Belgium

Bonjour guten MorgenGoede ochtend


SELECT TO_CHAR(hire_date,'DD.Mon.YYYY', 'NLS_DATE_LANGUAGE=FRENCH') FROM employeesWHERE hire_date > '01-JAN-2000';

SELECT last_name, first_name, TO_CHAR(salary,'99G999D99', 'NLS_NUMERIC_CHARACTERS='',.''') FROM employees;

Using NLS Parameters in SQL Functions


Using NLS Parameters in SQL Functions

Function

TO_DATE

NLS Parameter

NLS_DATE_LANGUAGENLS_CALENDAR

NLS_DATE_LANGUAGENLS_NUMERIC_CHARACTERSNLS_CURRENCYNLS_[ISO|DUAL]_CURRENCYNLS_CALENDAR

TO_CHAR, TO_NCHAR

TO_NUMBER NLS_NUMERIC_CHARACTERSNLS_CURRENCYNLS_[ISO|DUAL]_CURRENCY

NLS_UPPER, NLS_LOWER,NLS_INITCAP, NLSSORT

NLS_SORT


Linguistic Sorting

Sort order can be affected by:

• Case sensitivity

• Diacritics or accent characters

• Combination characters that are treated as a single character

• Phonetics or character appearance

• Cultural preferences


Linguistic Sorting

Three types of sorting:

• Binary sorting:– Sorted according to the binary values of the

encoded characters

• Monolingual linguistic sorting:– A two pass sort based on a character’s assigned

major and minor values

• Multilingual linguistic sorting– Based on the ISO standard (ISO 14651), and the

Unicode 3.2 Standard for multilingual collation– Ordered by the number of strokes, PinYin, or

radicals for Chinese characters


Using Linguistic Sorting

You can specify the type of sort used for character data with the:

• NLS_SORT parameter– Default value is derived from the NLS_LANG

environment variable, if set– Can be specified for the session, client, or server

• NLSSORT function – Defines the sorting method at the query

level


Sorts That Are Not Case or Accent Sensitive

SELECT cust_last_name FROM oe.customersWHERE cust_last_name = 'de Funes';

SELECT cust_last_name FROM oe.customersWHERE cust_last_name = NLS_UPPER('de Funes');

ALTER SESSION SET NLS_COMP=ANSI;ALTER SESSION SET NLS_SORT=GENERIC_BASELETTER;

SELECT cust_last_name FROM oe.customersWHERE cust_last_name = 'De Funes';


Linguistic Comparisons

• Use the NLS_COMP parameter to:– Perform linguistic comparisons instead of binary

comparisons– Avoid cumbersome statements involving the

NLSSORT function

• NLS_COMP can be set to:

– BINARY– ANSI

SELECT word FROM listWHERE word > 'gf';


Linguistic Index Support

• Create an index on linguistically sorted values

• Rapidly query data without having to specify ORDER BY clause and NLSSORT:

• Set the NLS_SORT parameter to match the linguistic definition you want to use for the linguistic sort when creating the index

CREATE INDEX list_word ON list (NLSSORT(word, 'NLS_SORT=French_M'));

SELECT word FROM list;


Customizing Linguistic Sorting

You can customize linguistic sorting for:

• Ignorable characters

• Contracting or expanding characters

• Special combination letters or special letters

• Expanding characters or special letters

• Special uppercase and lowercase letters

• Context-sensitive characters

• Reverse secondary sorting

• Canonical equivalence


Oracle Locale Builder


Character Set Scanner Utilities

• Character Set Scanner:– Scans the database to determine whether the

character set can be changed– Provides reports that detail possible problems and

fixes

• Language and Character Set File Scanner:– Determines the language and character set for

unknown file text– Uses probabilities to identify the dominant

language and character set


CREATE DATABASE ...CHARACTER SET WE8ISO8859P1NATIONAL CHARACTER SETUTF8...

% export NLS_LANG= American_America.US7ASCII

Data Conversion Between Client and Server Character Sets

C:/> set NLS_LANG= German_Germany.WE8DEC


NLS Data Conversion with Oracle Utilities

• Multiple data conversions can take place when data is exported from one database and imported into another if the same character sets are not used.

• External tables use the NLS settings on the server for determining the data character set.

• SQL*Loader:– Conventional Path: Data is converted into the

session character set specified by NLS_LANG.– Direct Path: Data is converted using client-side

directives.


NLS Data Conversion with Data Pump

• Data Pump Export always saves data in the same character set as the database from which the data originates.

• Data Pump Import converts the data to the character set of the target database, if needed.

• The Data Pump log file is written in the language specified by NLS_LANG for the session that started Data Pump.


Obtaining Character Set Information

SQL> SELECT parameter, value 2 FROM nls_database_parameters

3 WHERE parameter LIKE '%CHARACTERSET%';

PARAMETER VALUE----------------------- -------------NLS_CHARACTERSET WE8ISO8859P1NLS_NCHAR_CHARACTERSET AL16UTF16

2 rows selected.


Obtaining NLS Parameter Information

SQL> ALTER SESSION SET NLS_ISO_CURRENCY=FRANCE;

Session altered.

SQL> SELECT * FROM nls_instance_parameters

2 WHERE parameter LIKE '%ISO%';

PARAMETER VALUE----------------------- -------------NLS_ISO_CURRENCY AMERICA

SQL> SELECT * FROM nls_session_parameters

2 WHERE parameter LIKE '%ISO%';

PARAMETER VALUE----------------------- -------------NLS_ISO_CURRENCY FRANCE


Obtaining NLS Settings Information

• V$NLS_VALID_VALUES:Contains the values for NLS_LANGUAGE, NLS_SORT, NLS_TERRITORY and CHARACTERSET that are valid on your system

• V$NLS_PARAMETERS:– Contains the current NLS session settings,

including character sets– Used as the basis for NLS_SESSION_PARAMETERS


Summary

In this lesson, you should have learned how to:

• Customize language-dependent behavior for the database and individual sessions

• Specify different linguistic sorts for queries

• Retrieve data that matches a search string ignoring case or accent differences

• Obtain Globalization support configuration information


Practice 2 Overview: Using Globalization Support Features

This practice covers the following topics:

• Checking the database and national character set

• Identifying valid NLS values

• Setting NLS parameters

2 copyright © 2004, oracle. all rights reserved. using globalization support

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