关联查询一张小表。对性能有影响吗(mysql)
具体语句
SELECT dfm.id, dfm.member_code, dfm.member_name, dfm.recommend_code, dfm.member_rank, dfm.create_time, dfm.account, dfm.have_account, dfm.member_img, dfmr.rank_name, dfmr.grade_commission_ratio, dfm1.member_name AS recommendName FROM d_fx_member dfm LEFT JOIN d_fx_member_rank dfmr ON dfm.member_rank = dfmr.rank LEFT JOIN d_fx_member dfm1 ON dfm.recommend_code = dfm1.member_code WHERE dfm.member_code = 'zqy04'
人月神话:这个 没什么影响 只要数据量不超过10w
人月神话: 加大cache就ok
拼一个春夏秋冬.赢一个无悔人事。