PostgreSQL 的 WINDOW clause
PostgreSQL 的gram.y 中所说的 window_clause, 与 window 函数不同。
是一定要出现在 语句最后的:
create table a8(id integer, name varchar(10), salary integer);
insert into a8 values(1, 'aa', 1000);
insert into a8 values(2, 'bb', 3000);
insert into a8 values(3, 'cc', 2000);
insert into a8 values(4, 'dd', 5000);
insert into a8 values(5, 'ee', 2000);
insert into a8 values(6, 'ff', 4000);
insert into a8 values(2,'gg',2000);
SELECT
id, name, first_value(id) OVER w
FROM a8
WHERE salary>1000
WINDOW w AS ( PARTITION by id);
查询结果:
id name first_value
2 aa 2
2 gg 2
3 cc 3
4 dd 4
5 ee 5
6 ff 6