Question

I have checked the documentation provided by Oracle and found a way to modify a constraint without dropping the table. Problem is, it errors out at modify as it does not recognize the keyword.

Using EMS SQL Manager for PostgreSQL.

Alter table public.public_insurer_credit MODIFY CONSTRAINT public_insurer_credit_fk1
    deferrable, initially deferred;

I was able to work around it by dropping the constraint using :

ALTER TABLE "public"."public_insurer_credit"
  DROP CONSTRAINT "public_insurer_credit_fk1" RESTRICT;

ALTER TABLE "public"."public_insurer_credit"
  ADD CONSTRAINT "public_insurer_credit_fk1" FOREIGN KEY ("branch_id", "order_id", "public_insurer_id")
    REFERENCES "public"."order_public_insurer"("branch_id", "order_id", "public_insurer_id")
    ON UPDATE CASCADE
    ON DELETE NO ACTION
    DEFERRABLE 
    INITIALLY DEFERRED;

Answer 1

According to the correct manual (which is supplied by PostgreSQL, not by Oracle), there is no modify constraint available in the ALTER TABLE statement:

Here is the link to the correct manual:

http://www.postgresql.org/docs/current/static/sql-altertable.html