由MySQL删除查询SQL_CALC_FOUND_ROWS

Question

我想删除此查询返回的记录：

SELECT SQL_CALC_FOUND_ROWS tag, COUNT(tag) AS count 
FROM _tags 
GROUP BY tag 
HAVING count = 1 
ORDER BY count DESC 
LIMIT 100; 

我怎样才能做到这一点？

Answer 1

假设tag是_tags“主键：

DELETE _tags.* FROM _tags 
JOIN ( 
    SELECT tag FROM _tags GROUP BY tag HAVING COUNT(tag) = 1 LIMIT 100 
) AS subq USING (tag) 

不知道你的意思是 ”被删除SQL_CALC_FOUND_ROWS“。如果您只想知道有多少记录符合您的条件而忽略LIMIT条款，那么您应该首先运行SELECT。