采用：
SELECt * FROM OBJECTS o JOIN OBJECTSTAGS ot ON ot.object_id = o.id JOIN TAGS t ON t.id = ot.tag_id WHERe t.name IN ('tag1','tag2')GROUP BY o.id HAVINg COUNT(DISTINCT t.name) = 2您缺少HAVINg子句。
如果只需要两个标签都存在的行，则不需要LEFT JOIN。
采用：
SELECt * FROM OBJECTS o JOIN OBJECTSTAGS ot ON ot.object_id = o.id JOIN TAGS t ON t.id = ot.tag_id WHERe t.name IN ('tag1','tag2')GROUP BY o.id HAVINg COUNT(DISTINCT t.name) = 2您缺少HAVINg子句。
如果只需要两个标签都存在的行，则不需要LEFT JOIN。
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