CREATE TABLE subject (id_subj INTEGER NOT NULL PRIMARY KEY, subj_name VARCHAR(15), id_tch INTEGER, hour INTEGER); ALTER TABLE subject ADD CONSTRAINT FK_PREDMET_1 FOREIGN KEY (id_tch) REFERENCES teacher (id_tch) ON DELETE CASCADE ON UPDATE CASCADE

ALTER TABLE subject ADD CONSTRAINT FK_PREDMET_1 FOREIGN KEY (id_tch) REFERENCES VYKLAD(id_tch) ON DELETE CASCADE ON UPDATE CASCADE;

CREATE TABLE subject (id_subj INTEGER NOT NULL PRIMARY KEY, subj_name VARCHAR(15), id_tch INTEGER, CONSTRAINT FK_PREDMET_1 FOREIGN KEY (id_tch) REFERENCES teacher (id_tch), hour INTEGER)

CREATE DOMAIN hour AS INTEGER DEFAULT 50 CHECK (VALUE > 10);

ALTER TABLE subject (id_subj INTEGER NOT NULL PRIMARY KEY, subj_name VARCHAR(15), id_tch INTEGER, CONSTRAINT FK_PREDMET_1 FOREIGN KEY (id_tch) REFERENCES VYKLAD (id_tch), hour INTEGER CHECK(hour>0));