Data items and literals of class DBCS can be used in a relation condition with any relational operator. Each operand must be either a group item or of class DBCS. No conversion, editing, or de-editing is done; no distinction is made between items of category DBCS and items of category DBCS 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 will order them the same as in SBCS.
Where a character exists in both the DBCS and SBCS character sets, its DBCS and SBCS representations will not be regarded as equivalent. See the section Roman Script in DBCS.
The PROGRAM COLLATING SEQUENCE clause has no effect on comparisons involving data items of class DBCS or DBCS 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.