Composite Keys Defined by the User

If DBEngine does not find a suitable SET or DBGenFormat primary key, the DATABridge Client allows you to create a composite key. You can also create a composite key when the DATABridge Client decides to uses AA values as the primary key.

Note:

• If the added column is named "my_rsn," this indicates that it is an RSN, which makes an excellent key. Do not use composite keys when this is the case.
• You must not create a composite key for a data set that contains embedded data sets or for a data set that has other active data sets linking to it when the handling of DMSII links is enabled.

If a data set does not have a DBGenFormat primary key or a DMSII set that qualifies for use as an index, and the AA values are not valid, the set_name column in the DATASETS client control table is left blank. In this case, you can clone the data set, but you cannot track updates.

When the DMSII data set does not have a key, it is recommended that you create a composite key using the data set mapping customization script (script.user_layout.primary_tablename). See When to Use Composite Keys for more details about when to use a composite key.