php - MySQL 查询 - 获取列值 "greater than..."

Question

我有这个问题:

$score = 10;
SELECT timecode, count(tag) as n_tags, tag
FROM dados
WHERE dados.tag = 'tag1' 
AND dados.filename = 'file.mp4'
AND (timecode >= '-5' AND timecode <= '15')
AND (timecode = '$score')
GROUP BY timecode
ORDER BY count(tag) DESC

但是我想将第 6 行更改为:

AND (timecode = '$score' AND n_tags > 3)

但这似乎不是正确的做法，它不起作用。

有什么想法吗？

Answer 1

从 WHERE 子句中删除该行并放入 HAVING 子句。 HAVING 子句将查看聚合结果。 WHERE 没有。

SELECT timecode, count(tag) as n_tags, tag
FROM dados
WHERE dados.tag = 'tag1' 
AND dados.filename = 'file.mp4'
AND (timecode >= '-5' AND timecode <= '15')
AND (timecode = '$score')
GROUP BY timecode
HAVING count(tag) > 3
ORDER BY count(tag) DESC

此行是多余的，可以删除:AND (timecode >= '-5' AND timecode <= '15')

SELECT timecode, count(tag) as n_tags, tag
FROM dados
WHERE dados.tag = 'tag1' 
AND dados.filename = 'file.mp4'
AND (timecode = '$score')
GROUP BY timecode
HAVING count(tag) > 3
ORDER BY count(tag) DESC