我是mysql的新手。我有2个单独的查询,这些查询给了我数量。
我想得到[COUNT 1 - COUNT 2]。但是,我不知道如何在mysql中做到这一点。
以下是我的查询
(select COUNT(CITY) as M from STATION)
MINUS
(select COUNT(DISTINCT CITY) as N from STATION)
错误
ERROR 1064 (42000) at line 1: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '-
(select COUNT(DISTINCT CITY) as N from STATION)' at line 2
答案 0 :(得分:1)
您可以在单个查询中执行此操作,例如
SELECT COUNT(CITY) - COUNT(DISTINCT CITY)
FROM STATION
答案 1 :(得分:0)
解决
选择 ((从STATION选择COUNT(CITY)为M) 减去 (选择COUNT(DISTINCT CITY)作为ST的N))作为计数 来自STATION LIMIT 1
答案 2 :(得分:0)
尝试此查询!
选择
COUNT(CITY)
-
COUNT(DISTINCT CITY)
如
' M-N'
从
STATION