When to Use Primary Keys

DBEngine supports data sets regardless if they have unique key sets or not. Accessories, on the other hand, support data sets as follows:

• Span does not require that data sets have unique key sets.
• Snapshot requires data sets that don't have valid AAs, such as ORDERED and COMPACT, have a unique key set. If the dataset does not have a unique key set, you can define a primary key via the GenFormat program.
• DATABridge Clients require that data sets have unique key sets or valid AAs or RSNs. Use the GenFormat program to define primary keys for data sets, or set the key items manually in the client control tables.