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.

Figure 1. Foreign-key constraints