Foreign-key constraints

Express mode cannot disable primary constraints or unique constraints that are referenced as foreign keys that are active on other tables. If you want to load data into such a table, you must first use SET CONSTRAINTS DISABLED statements to disable the foreign-key constraints in the referencing table or tables. After the load is finished, re-enable the foreign-key constraints.

The following figure shows an example of foreign-key constraints. The table target has a primary key (thePK) and a unique key (unique) that table blue and table green reference. Before you perform an express-mode load into the table target, you must disable the foreign-key constraints in both table blue and table green.