>>-CHR--(--expression--)---------------------------------------><
The schema is SYSFUN.
Returns the character that has the ASCII code value specified by the argument.
The argument can be either INTEGER or SMALLINT. The value of the argument should be between 0 and 255; otherwise, the return value is null.
The result of the function is CHAR(1). The result can be null; if the argument is null, the result is the null value.