MySQL - 使用带计数的条件？

Question

我有以下sql语句：

select val, count(*) as tally from sometable group by val order by tally desc

生成以下（示例）表：

val | tally
----+-------
4   | 20
5   | 10
6   | 5
7   | 3
8   | 2

现在，我想只显示tally > 5所在的行，结果将是：

val | tally
----+-------
4   | 20
5   | 10

我尝试了这个陈述，但它没有用（它说“理货”未知）：

select val, count(*) as tally from sometable where tally > 5 group by val order by tally desc

Answer 1

尝试HAVING（more information）：

select val, count(*) as tally from sometable group by val having tally > 5 order by tally desc

Answer 2

您可以采取两种方法：

1：使用HAVING。这意味着将根据HAVING子句筛选查询结果，并且只会返回一些原始结果行：

SELECT val, COUNT( * ) AS tally
FROM sometable
GROUP BY val
ORDER BY tally DESC
HAVING tally > 5

2：使用子选择。这可能会给你带来更好的性能（我不是sql guru，所以我不能自信地说）：

SELECT val, tally
FROM (SELECT val, COUNT( * ) AS tally
      FROM sometable
      GROUP BY val
      ORDER BY tally DESC)
      temp
WHERE tally >1