FIELD (DBDGEN Statements)

There is a restriction of 512 bytes on the length of the key that IMS Option uses internally to store each segment in a database. This length is calculated by summing the lengths of the longest sequence field at each level in the database and adding two bytes for each level in the database. For non-unique sequence fields (SEQ,M), add four bytes to its sequence field length for this calculation. For non-keyed segments, use four bytes as its length for this calculation. If this limitation is exceeded, you see DBDGEN error message number DBDUT0L11.

For example, a database with just three segments, a root and two children of the root. The root sequence field is 10 bytes long, the first child's sequence field is 15 bytes long and the second child's sequence field is 25 bytes long. The sum of the key lengths at each level is 10 plus 25 for a total of 35. Adding two bytes for each of the levels in the database gives an IMS Option key length of 39.