When you reference the DB2 tables, DB2 rules relating to table names apply. That is, if your DB2 authorization ID is different from the ID under which the DB2 tables were created, you must use the qualified name. The qualified name consists of three parts: the authorization ID under which the DB2 table was created, followed by a period, then the table name. For example, use A12345.ENTITY_TYPE where A12345 is the authorization ID under which the table ENTITY_TYPE was created. Synonyms can be created and used. This guide uses the unqualified name.
Typically, you should qualify only the highest object in the selection with the model ID. For example, if you want to select entity types and their attributes, qualify entity type within model and attribute within entity type. For performance reasons, it can be advantageous to qualify all tables with model ID, if the join limits permit.
Important! If both entity type and attribute are qualified by model ID, but attribute is not qualified by entity type, a Cartesian product of the two tables results: The number of rows returned is the product of the number of rows selected from each table.
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