使用sql server 2005从另一个表更新多个列

Question

我有一个主表名称table1,我mobileNo每天存储或更新数据一个月.

;WITH table1 AS (SELECT * FROM (VALUES
(9999999999, '01/10/2013', NULL, NULL, NULL, NULL),
(9999999999, NULL, '02/10/2013', NULL, NULL, NULL),
(9999999999, NULL, NULL, '03/10/2013', NULL, NULL),
(9999999999, NULL, NULL, NULL, '04/10/2013', NULL),
(9999999999, NULL, NULL, NULL, NULL, '30/10/2013'),
(9999999999, NULL, NULL, NULL, NULL, NULL),
(8888888888, '01/10/2013', NULL, NULL, NULL, NULL),
(8888888888, NULL, '02/10/2013', NULL, NULL, NULL),
(8888888888, NULL, NULL, '03/10/2013', NULL, NULL),
(8888888888, NULL, NULL, NULL, '04/10/2013', NULL),
(8888888888, NULL, NULL, NULL, NULL, '30/10/2013')) 
as t(mobileno,date1,date2,date3,date4,date30))

我有另一个表名称table2 ,我mobileNo对table1 保持独特.现在我想更新table2,table1如果存在任何数据table1.

mobileno        date1      date2      date3      date4      date30
--------------- ---------- ---------- ---------- ---------- ----------
8888888888      01/10/2013 02/10/2013 03/10/2013 04/10/2013 30/10/2013
9999999999      01/10/2013 02/10/2013 03/10/2013 04/10/2013 30/10/2013

但是我尝试了这样的查询

UPDATE table1
set table1.date1 = 
(SELECT date1 from table2 where table2.mobileno = table1.mobileno) 
Where table2.mobileno = table1.mobileno

如何更新单个查询而不重复更新30个.日期列,请帮帮我.提前致谢.

Answer 1

也许可以使用以下UPDATE语句来避免来自TABLE2的NULL值到TABLE1中的UPDATE NOT NULL值.

只有ISNULL功能被添加到上一篇文章中

update table1
set 
    date1 = ISNULL(t2.date1, date1),
    date2 = ISNULL(t2.date2, date2)
from table2 t2
where table1.mobileno = t2.mobileno