数据排序 本文为您介绍如何在使用SELECT语法时进行排序。 按某一列排序 teledb create table teledbpg(id int, nickname text); CREATE TABLE teledb insert into teledbpg values(1,'teledb'),(3,'pg'),(1,'hello,pgxc'); COPY 3 teledb select from teledbpg order by nickname; id nickname + 1 hello,pgxc 3 pg 1 teledb (3 rows) 按第一列排序 teledb select from teledbpg order by 1; id nickname + 1 teledb 1 hello,pgxc 3 pg 按ID 升级排序,再按 nickname 降序排序 teledb select from teledbpg order by id,nickname desc; id nickname + 1 teledb 1 hello,pgxc 3 pg (3 rows) 效果与上面的语句一样。 teledb select from teledbpg order by 1,2 desc; id nickname + 1 teledb 1 hello,pgxc 3 pg (3 rows) 随机排序 teledb select from teledbpg order by random(); id nickname + 1 teledb 3 pg 1 hello,pgxc (3 rows) teledb select from teledbpg order by random(); id nickname + 1 hello,pgxc 1 teledb 3 pg (3 rows) 计算排序 teledb select from teledbpg order by md5(nickname); id nickname + 1 hello,pgxc 3 pg 1 teledb (3 rows) 排序也能用子查询。 teledb