When this variable is set at the default of TRUE (ON, or YES), A_SYB_ADD_IDENTITY adds an extra column to any table created by the Acu4GL for Sybase product. The extra column has identity property and is included on all indexes that are not unique. You do not have to code this column in your COBOL FD. On keys that allow duplicates, this variable has been found to vastly improve performance.

When A_SYB_ADD_IDENTITY is set to FALSE (OFF, or NO), an extra column is not added.

You can also add an identity column using the XFD directive IDENTITY-COLUMN. Using the XFD directive gives you greater control over where it appears.

You may only specify one identity column per table, and so after the first request has been processed, subsequent requests are ignored.