GROUP by和WHERE不能一起工作

Question

为什么此代码有效：

SELECT year, sum(value)
FROM test
GROUP BY year

这不是吗？

SELECT year, sum(value)
FROM test
GROUP BY year
WHERE `user` = 1

Answer 1

GROUP BY需要在WHERE之后：

SELECT year, sum(value) FROM test WHERE user = 1 GROUP BY year 

Answer 2

你试过吗

 SELECT year, sum(value) FROM test WHERE user = 1 GROUP BY year

Answer 3

我不是专家，但尝试“HAVING”条款：

SELECT year, sum(value)
FROM test
GROUP BY year
having `user` = 1

Answer 4

反转GROUP BY和WHERE条款：

SELECT year, SUM(value)
  FROM test
 WHERE user = 1
 GROUP BY year