这里有人帮助整理了这个非常有用的查询！
SELECT * FROM results r
INNER JOIN categories c on r.id = c.result_id
WHERE c.name in ('$purpose', '$prop_type', '$loan_type')
GROUP BY r.id
HAVING COUNT(c.c_id) = 3
LIMIT 50 OFFSET 0
哪个工作得很好！但是，当我尝试使用
SELECT * FROM results r
INNER JOIN categories c on r.id = c.result_id
WHERE c.name in ('$purpose', '$prop_type', '$loan_type')
ORDER BY r.usefulness DESC
GROUP BY r.id
HAVING COUNT(c.c_id) = 3
LIMIT 50 OFFSET 0
我收到语法错误。我在这里错过了一些明显的东西吗？
多谢！
查询
的各个部分有一个顺序，ORDER BY应该在最后（在LIMIT和OFFSET之前......试试这个：
SELECT * FROM results r
INNER JOIN categories c on r.id = c.result_id
WHERE c.name in ('$purpose', '$prop_type', '$loan_type')
GROUP BY r.id
HAVING COUNT(c.c_id) = 3
ORDER BY usefulness DESC
LIMIT 50 OFFSET 0
还要确保在任何行的末尾都有空格...
请注意，在MySQL中，这是LIMIT x OFFSET y的缩短版本 - 您可以编写LIMIT y,x
ORDER BY必须在HAVING之后出现。