一、mysql截取查詢清單中字段資料，用于統計（group by）
select count(*),SUBSTRING(a.managecom,1,6),b.name from t_agent a left join t_managecom b on SUBSTRING(a.managecom,1,6) = b.managecom where 1=1 GROUP BY SUBSTRING(a.managecom,1,6),name
一、mysql截取查詢清單中字段資料，用于統計（group by）
select count(*),SUBSTRING(a.managecom,1,6),b.name from t_agent a left join t_managecom b on SUBSTRING(a.managecom,1,6) = b.managecom where 1=1 GROUP BY SUBSTRING(a.managecom,1,6),name
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