数据过多时候,子查询改成left join减少笛卡尔积
摘要:
子查询 SELECT cn.portal_id AS portalId, count( id ) AS num FROM construction_package_wbs_node cn WHERE cn.delete_flag = 0 AND ( cn.node_type = '单位工程' OR 阅读全文
posted @ 2023-12-03 14:39 nitianxiaozi 阅读(104) 评论(0) 推荐(0)
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