怎么批量更新？

[xuguv]

两个表t1,t2,要求用t2的值来更新t1的值，即t1=sum（t2） 的值
如
t1:
id number
101 10
102 5
t2:
id quantity
101 51
101 100
101 80
102 50
102 90
最后的结果应该是
t1:
id numbwe
101 241
102 145

[發糞塗牆]

;
WITH    t2
          AS ( SELECT   id ,
                        SUM(quantity) quantity
               FROM     t2
               GROUP BY id
             )
    UPDATE  t1
    SET     t1.number = t2.quantity
    FROM    t1
            INNER JOIN t2 ON t1.id = t2.ID

[發糞塗牆]

--2000的写法

    UPDATE  t1
    SET     t1.number = t2.quantity
    FROM    t1
            INNER JOIN ( SELECT   id ,
                        SUM(quantity) quantity
               FROM     t2
               GROUP BY id
             ) t2 ON t1.id = t2.ID

[zhangbei59]

with那个 我感觉更清楚，易懂，2000的写法 很直接，可读性不强，，总之都非常红啊，楼主V5