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sql - How to Alter Constraint

SQL How to Alter Constraint

Below is 1 of my constraint

CONSTRAINT ACTIVEPROG_FKEY1 FOREIGN KEY(ActiveProgCode) REFERENCES PROGRAM(ActiveProgCode),

I want to add in

ON DELETE CASCADE

to the constraint above.

How do i alter that existing constraint ACTIVEPROG_FKEY1 and add

ON DELETE CASCADE

to constraint ACTIVEPROG_FKEY1

Consider ACTIVEPROG_FKEY1 is at Table ACTIVEPROG

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1 Answer

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You can not alter constraints ever but you can drop them and then recreate.

Have look on this

ALTER TABLE your_table DROP CONSTRAINT ACTIVEPROG_FKEY1;

and then recreate it with ON DELETE CASCADE like this

ALTER TABLE your_table
add CONSTRAINT ACTIVEPROG_FKEY1 FOREIGN KEY(ActiveProgCode) REFERENCES PROGRAM(ActiveProgCode)
    ON DELETE CASCADE;

hope this help


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