There is a class of data additional to the classes described in the section Class and Category of Data: it is called DBCS. It includes two data categories: DBCS and DBCS edited.
A data item of class DBCS is described by using the USAGE DISPLAY-1 clause. An item with this clause can have only the characters "G" and "B" in its PICTURE character-string. A " G" represents a DBCS character position; "B" is an editing character, and indicates a position that will always have a DBCS space inserted in editing. An item whose PICTURE character-string is all "G"s is of category DBCS; an item whose PICTURE character-string contains both "G" s and "B"s is of category DBCS edited.
Note that each "G" or "B" represents one 2-byte character position. Except where otherwise stated, the length of the data item for all purposes is the number of "G" s and "B"s in its PICTURE character-string.
For reference modification, the leftmost-character-position and length specify the number of DBCS characters, not bytes.
Data items of class DBCS can be used wherever data items of class alphanumeric can be used, subject to rules and exceptions given in the appropriate places in this chapter.