YanQiuXiang

PostgreSQL的常用时间函数使用整理如下： 一、获取系统时间函数 1.1 获取当前完整时间 select now(); david=# select now(); now ------------------------------- 2013-04-12 15:39:40.399711+08 (1 row

alter table bi_appinfo alter  COLUMN  uid  type character varying(100) ;

select * from( select row_number() over(partition by from_id,createtime order by nickname) as flag,* from( SELECT  from_id,max(createtime) as createtime,isread as nickname  FROM  comments  WHERE