String functions

Db2 supports various string functions that are defined by ODBC using vendor escape clauses.

The following rules apply to input strings for these functions:

Character string literals used as arguments to scalar functions must be enclosed in single quotes.
Arguments denoted as string_exp can be the name of a column, a string literal, or the result of another scalar function, where the underlying data type can be represented as SQL_CHAR, SQL_VARCHAR, or SQL_LONGVARCHAR.
Arguments denoted as start, length, code, or count can be a numeric literal or the result of another scalar function, where the underlying data type is integer based (SQL_SMALLINT, SQL_INTEGER).
The first character in the string is considered to be at position 1.

ASCII( string_exp ): Returns the ASCII code value of the leftmost character of string_exp as an integer.

CONCAT( string_exp1, string_exp2 ): Returns a character string that is the result of concatenating string_exp2 to string_exp1.

INSERT( string_exp1, start, length, string_exp2 ): Returns a character string where length number of characters beginning at start is replaced by string_exp2 which contains length characters.

LEFT( string_exp, count ): Returns the leftmost count of characters of string_exp.

LENGTH( string_exp ): Returns the number of characters in string_exp, excluding trailing blanks and the string termination character.

REPEAT( string_exp, count ): Returns a character string composed of string_exp repeated count times.

RIGHT( string_exp, count ): Returns the rightmost count of characters of string_exp.

SUBSTRING( string_exp, start, length ): Returns a character string that is derived from string_exp beginning at the character position specified by start for length characters.