mysql in 子查詢 效率慢，對比

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 desc SELECT id,detail,groupId from hs_knowledge_point where groupId in (    SELECT groupId from hs_knowledge_point where groupId>0 GROUP BY groupId HAVING COUNT(groupId) > 1     UNION all    SELECT groupId from hs_knowledge_point_commit where groupId>0 GROUP BY groupId HAVING COUNT(groupId) > 1 )UNION ALLSELECT id,detail,groupId from hs_knowledge_point_commit where groupId in (    SELECT groupId from hs_knowledge_point where groupId>0 GROUP BY groupId HAVING COUNT(groupId) > 1     UNION all    SELECT groupId from hs_knowledge_point_commit where groupId>0 GROUP BY groupId HAVING COUNT(groupId) > 1 )

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SELECT id,detail,groupId from hs_knowledge_point where groupId in (    select groupId from (        SELECT groupId from hs_knowledge_point where groupId>0 GROUP BY groupId HAVING COUNT(groupId) > 1         UNION all        SELECT groupId from hs_knowledge_point_commit where groupId>0 GROUP BY groupId HAVING COUNT(groupId) > 1     ) tmp)UNION ALLSELECT id,detail,groupId from hs_knowledge_point_commit where groupId in (    select groupId from (        SELECT groupId from hs_knowledge_point where groupId>0 GROUP BY groupId HAVING COUNT(groupId) > 1         UNION all        SELECT groupId from hs_knowledge_point_commit where groupId>0 GROUP BY groupId HAVING COUNT(groupId) > 1     ) tmp)

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mysql in 子查詢 效率慢，對比