# Metadata for Key Generation

The required table metadata that is used by the key generator indicates:

- The type of key, e.g. whether it is system-generated or sequential
- The key table in which key values are stored
- The length of the inherited portion of the key.

Example Table Metadata Key Information

In the Service Agreement table metadata example above, the metadata key information is shown by the values in the fields Key Table, Type of Key and Inherited Key Prefix Length.

The primary key constraint is used to retrieve the name of the key field for the table from the field metadata.

The field metadata provides the field data type and length.

Note: Key Types. Although there are more types of keys indicated in metadata drop-down list, the only types currently supported by the key generator in the Oracle Utilities Application Framework are system-generated and sequential.
Note: Special Annotation. If a table's inherited key prefix length is non-zero, a special entry "clusteringParentProperty" must be in the business entity annotation for this table.
Parent topic: Key Generation