Choosing Physical Tuning Options › Relationship Tuning Options › Removing Foreign Keys

Removing Foreign Keys

Since all defined relationships in a database implemented with non-SQL are linked, you have the option of removing foreign keys from the child entity. This:

• Reduces storage requirements
• Eliminates the need to update each child occurrence if the parent's key is changed

If you choose to retain the embedded foreign keys, you:

• Have full update SQL access to the data
• Might reduce the number of I/Os required to retrieve foreign key values for nonclustered entities (for example, to retrieve the department ID of an employee)