CHAR function

The CHAR function returns a fixed-length character string representation.

The representations are:

A character string, if the first argument is any type of character string.
A datetime value, if the first argument is a date, time, or timestamp.
A decimal number, if the first argument is a decimal number.
A double-precision floating-point number, if the first argument is a DOUBLE or REAL.
An integer number, if the first argument is a SMALLINT, INTEGER, or BIGINT.

The first argument must be of a built-in data type. The result of the CHAR function is a fixed-length character string. If the first argument can be null, the result can be null. If the first argument is null, the result is the null value. The first argument cannot be an XML value. To convert an XML value to a CHAR of a specified length, you must use the SQL/XML serialization operator XMLSERIALIZE.

Character to character syntax

CHAR (CharacterExpression [, integer] )

CharacterExpression: An expression that returns a value that is CHAR, VARCHAR, LONG VARCHAR, or CLOB data type.
integer: The length attribute for the resulting fixed length character string. The value must be between 0 and 254.

If the length of the character-expression is less than the length attribute of the result, the result is padded with blanks up to the length of the result. If the length of the character-expression is greater than the length attribute of the result, truncation is performed. A warning is returned unless the truncated characters were all blanks and the character-expression was not a long string (LONG VARCHAR or CLOB).

Integer to character syntax

CHAR (IntegerExpression )

IntegerExpression: An expression that returns a value that is an integer data type (either SMALLINT, INTEGER or BIGINT).

The result is the character string representation of the argument in the form of an SQL integer constant. The result consists of n characters that are the significant digits that represent the value of the argument with a preceding minus sign if the argument is negative. It is left justified.

If the first argument is a small integer: The length of the result is 6. If the number of characters in the result is less than 6, then the result is padded on the right with blanks to length 6.
If the first argument is a large integer: The length of the result is 11. If the number of characters in the result is less than 11, then the result is padded on the right with blanks to length 11.
If the first argument is a big integer: The length of the result is 20. If the number of characters in the result is less than 20, then the result is padded on the right with blanks to length 20.

Datetime to character syntax

CHAR (DatetimeExpression )

DatetimeExpression

An expression that is one of the following three data types:

date: The result is the character representation of the date. The length of the result is 10.
time: The result is the character representation of the time. The length of the result is 8.
timestamp: The result is the character string representation of the timestamp. The length of the result is 26.

Decimal to character

CHAR (DecimalExpression )

DecimalExpression: An expression that returns a value that is a decimal data type. If a different precision and scale is desired, the DECIMAL scalar function can be used first to make the change.

Floating point to character syntax

CHAR (FloatingPointExpression )

FloatingPointExpression: An expression that returns a value that is a floating-point data type (DOUBLE or REAL).

Use the CHAR function to return the values for EDLEVEL (defined as smallint) as a fixed length character string:

SELECT CHAR(EDLEVEL) FROM EMPLOYEE

An EDLEVEL of 18 would be returned as the CHAR(6) value '18????????' (18 followed by four blanks).