oracle sql
DESCRIPTION
Oracle SQL. Character Functions. Overview. A Function is a type of formula whose result is one of two things: A transformation Such as changing a student’s name to upper case letters Information Such as finding the length of a word in a column - PowerPoint PPT PresentationTRANSCRIPT
Oracle SQL Character Functions
Overview
A Function is a type of formula whose result is one of two things:
A transformation
Such as changing a student’s name to upper case letters
Information
Such as finding the length of a word in a column
Functions are named and usually require at least one parameter
All functions in this section perform the transformation/information on a single row of the table
Aggregate functions perform against multiple rows
Data Types
Each value in a table row has a data type associated with it
A data type determines the value’s attributes and acceptable values
123 is a number data type
“abc” is a text data type
“abc” is NOT a number data type
Most SQL operations use the following data types:
NUMBER
VARCHAR2
DATE
Reading Function Syntax Diagrams
[ ] Square brackets enclose syntax options
{ } Braces enclose items of which only one is required
| A vertical bar denotes options
… Three dots indicate that the preceding expression can be repeated
Delimiters
Example of delimiters are commas and parentheses, etc.
CAPS Indicate Oracle keywords
UNDERLINE
Indicates a default value
Syntax Symbols
Character Functions
LOWER(string1) Converts to lowercase
UPPER(string1) Converts to uppercase
INITCAP(string1) Capitalizes the first letter
LPAD( string1, padded_length, [ pad_string ] )
Left pads
RPAD( string1, padded_length, [ pad_string ] )
Right pads
LTRIM( string1, [ trim_string ] ) Left trims
RTRIM( string1, [ trim_string ] ) Right trims
Character Functions
Character Functions
TRIM([LEADING|TRAILING|BOTH] trim_character FROM string1)
Trims leading, trailing or both sides
SUBSTR( string1, start_position, [ length ] ) Cuts out a piece of a string
INSTR( string1, string2 [, start_position [, nth_appearance ] ] )
Determines the starting location of a string
Character Functions continued
Character Functions
LENGTH(string1) Returns the length of a string
CONCAT(string1,string2) Concatenates two strings
REPLACE( string1, string_to_replace, [ replacement_string ] )
Replaces a string with another string
SOUNDEX(string1) Returns phonetic representation
TRANSLATE( string1, string_to_replace, replacement_string )
Substitutes individual characters
Character Functions continued
Character Functions Practice
Write a query to show the city within the zipcode table as all capital letters, all lower case letters and mixed case letters
Use one query to show all three variations
Write a query to return the first 3 letters of a student’s last name from the student table
Write a query to display the length of each student’s last name
Using the CONCAT function, concatenate cities and states together (zipcode table)
Now use ||’s to add a comma and space
New York, NY
Using SOUNDEX list all last names that sound like ‘MARTIN’ (student table)
Hint: use a Where soundex (last_name) = soundex (‘MARTIN’) clause
For March 10th
Number Functions
Quiz
Project 10 is due