select a,b from
(
select avg(a) from table where...... ,
select b from table where ......
)里面两个子查询完成,就可以了~ 应该很简单吧
(
select avg(a) from table where...... ,
select b from table where ......
)里面两个子查询完成,就可以了~ 应该很简单吧
SELECT B FROM TABLE WHERE DATA=(SELECT MAX(DATA) FROM TABLE) 得到最大DATA对应的B值
SELECE AVG(A)FROM TABLE WHERE DATA >STARTDATA AND DATA<ENDDATA 得到A平均值就是实现以上两个语句中的 A 、B值 用一次查询都查出来
(
SELECT AVG(T_CYG1G) FROM T2_P_WS_SJCJ ,
SELECT T_CYG2G FROM T2_P_WS_SJCJ WHERE D_RIQI=(SELECT MAX(D_RIQI) FROM T2_P_WS_SJCJ)
)
提示:invalid table name表名一定存在,帮忙看看哪写错了?
改为
SELECT AVG(T_CYG1G) AS T_CYG1G FROM T2_P_WS_SJCJ
SELECT T_CYG2G FROM T2_P_WS_SJCJ WHERE D_RIQI=(SELECT MAX(D_RIQI) FROM T2_P_WS_SJCJ)这两个查询单独执行都可以通过怎么才可以把他们放一起啊,大虾快来救命啊!!
把FROM后面的一对 ()去掉~ 就可以了
(select max(a) a from test) ,
(select avg(b) b from test) 参考一下我刚调试成功的例子吧~ from后面不能加(), 子查询必须加 ()
(
SELECT AVG(T_CYG1G) AS T_CYG1G,T_CYG2G FROM T2_P_WS_SJCJ WHERE D_RIQI=(SELECT MAX(D_RIQI) FROM T2_P_WS_SJCJ))
(select max(a) a from test) ,
(select avg(b) b from test) 这是我刚调试成功的~ 绝对可以, 你照这个样子把里面的子查询改一下
(SELECT AVG(T_CYG1G) AS T_CYG1G FROM T2_P_WS_SJCJ),
(SELECT T_CYG2G FROM T2_P_WS_SJCJ WHERE D_RIQI=(SELECT MAX(D_RIQI) FROM T2_P_WS_SJCJ))OK!
成功,谢谢 benny0526()
能否帮忙推荐些关于这方面的资料?