CREATE TABLE seans
(
	idseans INT NOT NULL PRIMARY KEY IDENTITY,
	sfilm INT NOT NULL,
	datepokaz DATE NOT NULL,
	vrpokaz TIME(0) NOT NULL,
	stoimost MONEY NOT NULL,
	szal INT NOT NULL,
)

CREATE TABLE bilety
(
	idbil INT NOT NULL PRIMARY KEY IDENTITY,
	bseans INT NOT NULL,
	kolbil INT NOT NULL,
	summa MONEY,
	FOREIGN KEY (bseans) REFERENCES seans (idseans)
)

CREATE TABLE zal 
(
	idzal INT NOT NULL PRIMARY KEY IDENTITY,
	zfilial INT NOT NULL,
	znaz VARCHAR(25) NOT NULL,
	kolmest INT NOT NULL,
	tip VARCHAR(25) NOT NULL
	FOREIGN KEY (zfilial) REFERENCES filial (idfilial)
)

CREATE TRIGGER bilet_summa
ON bilety
FOR INSERT, UPDATE
AS

UPDATE bilety
	SET summa = b.kolbil * s.stoimost
	FROM bilety AS b
	JOIN seans AS s ON b.bseans = s.idseans