SQL怎么查询某个时间的上一次时间?答:SELECT USERNAME, TRADETIME, TRADE_NO, -- LAG(TRADETIME,1) 上一个TRADETIME -- PARTITION BY USERNAME,SUBSTR(TRADE_NO, 1, 1) 根据 USERNAME 和 TRADE_NO 的第一个字母进行分组 LAG(TRADETIME, 1) OVER(PARTITION BY USERNAME,SUBSTR(TRADE_NO, 1, 1) ORDER BY TRADETIME) ...
oracle数据库里面的字符串转成数字类型,答:insert into a values (1,'aa');insert into a values (2,'bb');insert into a values (3,'cc');cimmit;取当前行的前一行数据 select id,name,lag(id,1)over(order by id),lag(name,1)over(order by id) from a where id in (2,3);取当前行的后一行数据 select id,name,lead...