On 12/7/20 1:27 PM, Tom Lane wrote:
Ron <ronljohnsonjr@gmail.com> writes:
Neither technique worked.
test=# ALTER TABLE sales_detail ALTER CONSTRAINT
fk_sales_detail_sales_header DEFERRABLE INITIALLY DEFERRED;
ALTER TABLE
Hmm, reproduced here. There seems to be some kind of bug
in ALTER CONSTRAINT --- it looks like it's updated all the
child FKs successfully, but it actually hasn't. If you
drop the FK constraint altogether, and recreate it having
DEFERRABLE INITIALLY DEFERRED from the start, it should
work --- at least it does for me.
That works
sometimes, but not when we
really want it to work.
test=# alter table sales_detail drop CONSTRAINT fk_sales_detail_sales_header;
ALTER TABLE
test=# ALTER TABLE sales_detail
test-# ADD CONSTRAINT fk_sales_detail_sales_header
test-# FOREIGN KEY (cust_id, order_ts)
test-# REFERENCES sales_header (cust_id, order_ts) DEFERRABLE INITIALLY DEFERRED;
ALTER TABLE
test=#
test=#
-- Works
test=# begin transaction;
BEGIN
test=# delete from sales_header where cust_id = 1;
DELETE 3
test=#
test=# rollback;
ROLLBACK
-- Does not work
test=# begin transaction;
BEGIN
test=# ALTER TABLE sales_header DETACH PARTITION sales_header_202001;
ERROR: removing partition "sales_header_202001" violates foreign key constraint "sales_detail_cust_id_order_ts_fkey"
DETAIL: Key (cust_id, order_ts)=(1, 2020-01-05 13:05:42.567) is still referenced from table "sales_detail".
test=# rollback;
ROLLBACK--
Angular momentum makes the world go 'round.
