Question

for each value in the foreign key field, a corresponding value may or may not appear in the primary key field. true or false​

Answer 1

Answer:

True

Explanation:

an attempt is made to delete the row in a primary key table or to change a primary key value, the action will fail when the deleted or changed primary key value corresponds to a value in the foreign key constraint of another table. To successfully change or delete a row in a foreign key constraint, you must first either delete the foreign key data in the foreign key table or change the foreign key data in the foreign key table, which links the foreign key to different primary key data.