A key specification ( key spec ) allows rows in a table to be located whose key column values match the values in the key specification. A row containing the specified key values does not have to exist.

column name, value spec

The value specification ( value spec ) must not be NULL.

The column name must identify a key column in the table.

The key specification must contain all the key columns in a table. The individual key specifications ( key spec ) must be separated by commas.

For tables defined without key columns, there is the implicitly generated column SYSKEY CHAR(8) BYTE which contains a key generated by the database system. This column can only be used in a key specification.