Binary string assignments
The following rules apply when the assignment target is a binary string.
Storage assignment
The basic rule is that the length of a string assigned to a column, parameter of a function or procedure, or transition variable must not be greater than the length attribute of the column or parameter. If the string is longer than the length attribute of that column, parameter, or transition variable, an error is returned. Trailing hexadecimal zeroes (X'00') are normally included in the length of the string. For storage assignments, however, trailing hexadecimal zeroes are not included in the length of the string.
When a string is assigned to a fixed-length binary-string column, parameter, or transition variable and the length of the string is less than the length attribute of the target, the string is padded on the right with the necessary number of hexadecimal zeroes.
Retrieval assignment
The length of a string assigned to a variable (but not a parameter or transition variable) can be greater than the length attribute of the variable. When a string is assigned to a variable and the string is longer than the length attribute of the variable, the string is truncated on the right by the necessary number of bytes. When this occurs, an SQLSTATE of '01004' is assigned to the RETURNED_SQLSTATE condition area item in the SQL Diagnostics Area (or the value 'W' is assigned to the SQLWARN1 field of the SQLCA).
When a string is assigned to a fixed-length binary-string variable and the length of the string is less than the length attribute of the target, the string is padded on the right with the necessary number of hexadecimal zeroes.
When a string of length n is assigned to a varying-length string variable with a maximum length greater than n, the bytes after the nth byte of the variable are undefined.