SQL string functions

The table is created relative to MS SQL Server string functions set.

Function Name	Description
ASCII()	Returns the ASCII code value of the leftmost character of a string. SELECT ASCII('A') AS AsciiValue; -- 65
CHAR()	Returns a character based on its ASCII code value. SELECT CHAR(65) AS Character; -- A
CONCAT()	Concatenates two or more strings together. SELECT CONCAT('John', ' ', 'Doe') AS FullName; -- John Doe
CONCAT_WS()	Concatenates multiple strings together with a specified separator. SELECT CONCAT_WS(', ', 'John', 'Doe', '123 Main St.') AS Address; -- John, Doe, 123 Main St.
DIFFERENCE()	Compares two strings and returns an integer that represents the difference between them. SELECT DIFFERENCE('apple', 'apples') AS Difference; -- 2
FORMAT()	Formats a value with a specified format mask. SELECT FORMAT(12345.6789, '#,##0.00') AS FormattedValue; -- 12,345.68
LEFT()	Returns a specified number of characters from the left side of a string. SELECT LEFT('John Doe', 4) AS FirstName; -- John
LEN()	Returns the length of a string. SELECT LEN('John Doe') AS NameLength; -- 8
LOWER()	Returns a string in lowercase. SELECT LOWER('JOHN DOE') AS LowerName; -- john doe
LTRIM()	Removes leading spaces from a string. SELECT LTRIM(' John Doe ') AS TrimmedName; -- 'John Doe '
NCHAR()	Returns a Unicode character based on its Unicode code value. SELECT NCHAR(65) AS UnicodeChar; -- A
PATINDEX()	Returns the starting position of a pattern in a string. SELECT PATINDEX('%do%', 'John Doe') AS Position; -- 6
QUOTENAME()	Encloses a string in square brackets and escapes any embedded brackets within the string. SELECT QUOTENAME('MyTable') AS TableName; -- [MyTable]
REPLACE()	Replaces all occurrences of a specified string with another specified string. SELECT REPLACE('Hello, World!', 'World', 'SQL') AS Result; -- Hello, SQL!
REPLICATE()	Repeats a string a specified number of times. SELECT REPLICATE('SQL ', 3) AS Result; -- SQL SQL SQL
REVERSE()	Returns the reverse of a string. SELECT REVERSE('Hello, World!') AS Result; -- !dlroW ,olleH
RIGHT()	Returns a specified number of characters from the right side of a string. SELECT RIGHT('Hello, World!', 6) AS Result; World!
RTRIM()	Removes all trailing spaces from a string. SELECT RTRIM(' SQL ') AS Result; -- SQL
SPACE()	Returns a string of spaces of the specified length. SELECT SPACE(5) + 'SQL' AS Result; --      SQL
STUFF()	Deletes a specified length of characters from a string and inserts another string at the specified starting position. -- SELECT STUFF('Hello, World!', 7, 5, 'SQL') AS Result; Hello, SQL!
SUBSTRING()	Returns a specified part of a string. SELECT SUBSTRING('Hello, World!', 1, 5) AS Result; -- Hello
TRANSLATE()	Replaces a set of characters in a string with another set of characters. SELECT TRANSLATE('Hello, World!', 'oe', 'EO') AS Result; -- HEllo, WOrld!
TRIM()	Removes all leading and trailing spaces from a string. SELECT TRIM(' SQL  ') AS Result; -- SQL
UNICODE()	Returns the Unicode value of the first character in a string. SELECT UNICODE('A') AS Result; -- 65
UPPER()	Converts all characters in a string to uppercase. SELECT UPPER('Hello, World!') AS Result; -- HELLO, WORLD!