select abstractInfo, substring(brandName,1,charindex('-',brandName)-1) brand,brandname,sum(num) total from ( select id, brandname ,brandBatch,status,abstractInfo,inStock,nowStock,outStock,createDateTime,cargoSpace,(case when abstractInfo='入库' then inStock when abstractInfo='出库' then outStock else '' end) numfrom dbo.inOutStockInfo where abstractInfo='${type}' and status <>'营销物资' and datediff(year,createDateTime,getdate())=0 ) a group by abstractInfo,substring(brandName,1,charindex('-',brandName)-1),brandname把charindex('-',brandName)-1 改为10,OKSQLserver 是否对 substring 函数长度做限制?substring(brandName,1,charindex('-',brandName)-1) 如何减少嵌套层数?