forum.lissyara.su

Код: Выделить всё

test=# CREATE TABLE TEST (
test(# id serial PRIMARY KEY,
test(# description varchar NOT NULL UNIQUE
test(# );
CREATE TABLE
test=# INSERT INTO test (description) VALUES ('1');
INSERT 0 1
test=# SELECT * FROM test;
 id | description
----+-------------
  1 | 1
(1 строка)

test=# INSERT INTO test (description) VALUES ('1');
ERROR:  duplicate key value violates unique constraint "test_description_key"
ПОДРОБНОСТИ:  Key (description)=(1) already exists.
test=# INSERT INTO test (description) VALUES ('2');
INSERT 0 1
test=# SELECT * FROM test;
 id | description
----+-------------
  1 | 1
  3 | 2
(2 строки)

test=#