For each table, OpenEdge computes a CRC value (database CRC) from selected elements of the table metaschema. When compiling a procedure, OpenEdge inserts the database CRC for each database table the procedure accesses. The database CRC for each table is stored in the metaschema _File record _CRC field for the table. A matching CRC ensures that the schema referenced by the r-code is compatible with the table schema.

CRCs help maintain database integrity. CRCs change only when certain schema elements critical to field or record definitions change. As long as a table is structurally compatible with the r-code that references it, the CRCs match and the r-code can execute. It does not matter when or where the table's schema was created or updated.