1 為表和列創(chuàng)建備注

drop table if exists test;
create table test(
objectid serial not null,
num integer not null,
constraint pk_test_objectid primary key (objectid),
constraint ck_test_num check(num < 123 ),
);
comment on table test is ‘我是表’;
comment on column test.objectid is ‘我是唯一主鍵’;
comment on column test.num is ‘數(shù)量字段’;
comment on constraint pk_test_objectid on test is ‘我是約束,唯一主鍵’;
comment on constraint ck_test_num on test is ‘我是約束,num字段必須小于123’;
dS+ test;