-- 将当前数据库中, 所有表的smalldatetime 列改为nvarchar(20)
-- 如果列上有索引/默认值之类的依赖项, 则无法修改
EXEC sp_msforeachtable
@command1 = N'
DECLARE CUR CURSOR LOCAL
FOR
SELECT
N''ALTER TABLE ? ALTER COLUMN ''
+ QUOTENAME(C.name)
+ N''nvarchar(20)''
FROM syscolumns C, systypes T
WHERE C.xusertype = T.xusertype
AND T.name = ''smalldatetime''
AND C.id = OBJECT_ID(N''?'')
OPEN CUR
DECLARE @s nvarchar(4000)
FETCH CUR INTO @s
WHILE @@FETCH_STATUS = 0
BEGIN
PRINT(@s)
EXEC(@s)
FETCH CUR INTO @s
END
CLOSE CUR
DEALLOCATE CUR
',
@whereand = N'
AND EXISTS(
SELECT * FROM syscolumns C, systypes T
WHERE C.xusertype = T.xusertype
AND T.name = ''smalldatetime''
AND C.id = O.id)
'
