Data items and literals of class NCHAR can be used in a relation condition with any relational operator. No conversion, editing or de-editing is done and no distinction is made between items of category NCHAR and items of category NCHAR-EDITED.
The operation performed is a nonnumeric comparison. Since there is in general no collating sequence between the characters in a DBCS character set, the collating sequence used is based on the numeric values of the bit patterns representing the characters, interpreted as if they were binary numbers.
Note that if the DBCS character codes include codes for characters in the SBCS character set, there is no guarantee that this collating sequence orders them the same as in SBCS.
Where a character exists in both the DBCS and SBCS character sets, its DBCS and SBCS representations are not regarded as equivalent.
The PROGRAM COLLATING SEQUENCE clause has no effect on comparisons involving data items of class NCHAR or NCHAR literals.
If the operands are of unequal size, comparison proceeds as though the shorter operand were extended on the right by enough DBCS spaces to make them the same size.