SELECT Aggregate和UPDATE - SQL Server

Question

SQL Server初学者在这里.我在SELECT/UPDATE语句上遇到了一些麻烦.我有一个包含订单号列和行号列的表.下面的select语句返回我想要的值.我想获取结果并将该数字插入到订单号匹配的同一个表的列中.我在想这个吗？或者可能在考虑复杂性？:)

    SELECT
    ORDNUM, COUNT(LINNUM) AS 'CountLines'
    FROM [TableName]
    WHERE STS = '3' AND DUEQTY < ONHAND AND STYPE = 'CU'
    GROUP BY ORDNUM

    UPDATE [TableName]
    SET LNCNT = 'CountLines'
    WHERE ORDNUM = ORDNUM

先感谢您.本

更新:我在下面使用了Andomars解决方案,效果很好.谢谢大家的帮助.

Answer 1

使用SQL Server语法:

update  tn
set     LNCNT = SubQuery.CountLines
from    TableName as tn
join    (
        select  ordnum
        ,       count(linnum) as CountLines
        from    TableName
        where   sts = '3'
                and DUEQTY < ONHAND 
                and STYPE = 'CU'
        group by
                ordnum
        ) as SubQuery
on      SubQuery.ordnum = tn.ordnum