Може да се накара да работи, тригерът, който извършва преместването, просто трябва да бъде дефиниран за всеки дял, а не за цялата таблица. Така че започнете, както направихте за дефинициите на таблици и тригера INSERT
CREATE TABLE records (
record varchar(64) NOT NULL,
active boolean default TRUE
);
CREATE TABLE active_records (CHECK (active)) INHERITS (records);
CREATE TABLE inactive_records (CHECK (NOT active)) INHERITS (records);
CREATE OR REPLACE FUNCTION record_insert()
RETURNS TRIGGER AS $$
BEGIN
IF (TRUE = NEW.active) THEN
INSERT INTO active_records VALUES (NEW.*);
ELSE
INSERT INTO inactive_records VALUES (NEW.*);
END IF;
RETURN NULL;
END;
$$
LANGUAGE plpgsql;
CREATE TRIGGER record_insert_trigger
BEFORE INSERT ON records
FOR EACH ROW EXECUTE PROCEDURE record_insert();
... нека имаме малко тестови данни ...
INSERT INTO records VALUES ('FirstLittlePiggy', TRUE);
INSERT INTO records VALUES ('SecondLittlePiggy', FALSE);
INSERT INTO records VALUES ('ThirdLittlePiggy', TRUE);
INSERT INTO records VALUES ('FourthLittlePiggy', FALSE);
INSERT INTO records VALUES ('FifthLittlePiggy', TRUE);
Сега тригерите на дяловете. Проверката if NEW.active =OLD.active се подразбира при проверката на стойността на active, тъй като знаем какво е позволено да бъде в таблицата на първо място.
CREATE OR REPLACE FUNCTION active_partition_constraint()
RETURNS TRIGGER AS $$
BEGIN
IF NOT (NEW.active) THEN
INSERT INTO inactive_records VALUES (NEW.*);
DELETE FROM active_records WHERE record = NEW.record;
RETURN NULL;
ELSE
RETURN NEW;
END IF;
END;
$$
LANGUAGE plpgsql;
CREATE TRIGGER active_constraint_trigger
BEFORE UPDATE ON active_records
FOR EACH ROW EXECUTE PROCEDURE active_partition_constraint();
CREATE OR REPLACE FUNCTION inactive_partition_constraint()
RETURNS TRIGGER AS $$
BEGIN
IF (NEW.active) THEN
INSERT INTO active_records VALUES (NEW.*);
DELETE FROM inactive_records WHERE record = NEW.record;
RETURN NULL;
ELSE
RETURN NEW;
END IF;
END;
$$
LANGUAGE plpgsql;
CREATE TRIGGER inactive_constraint_trigger
BEFORE UPDATE ON inactive_records
FOR EACH ROW EXECUTE PROCEDURE inactive_partition_constraint();
... и тествайте резултатите ...
scratch=> SELECT * FROM active_records;
record | active
------------------+--------
FirstLittlePiggy | t
ThirdLittlePiggy | t
FifthLittlePiggy | t
(3 rows)
scratch=> UPDATE records SET active = FALSE WHERE record = 'ThirdLittlePiggy';
UPDATE 0
scratch=> SELECT * FROM active_records;
record | active
------------------+--------
FirstLittlePiggy | t
FifthLittlePiggy | t
(2 rows)
scratch=> SELECT * FROM inactive_records;
record | active
-------------------+--------
SecondLittlePiggy | f
FourthLittlePiggy | f
ThirdLittlePiggy | f
(3 rows)