实际使用例子：
/*--将所需表的某特定数值类型批量转换为其他类型--*/
/*--调用示例:E1T04_1996 char(10)-转换为nvarchar(100) --*/
set ANSI_NULLS ON
set QUOTED_IDENTIFIER ON
go
CREATE procedure [dbo].[p_set]
as
declare tb cursor for
SELECT sql='alter table ['+d.name+'] alter column ['+a.name+'] nvarchar'
+' (100)' FROM syscolumns a
left join systypes b on a.xtype=b.xusertype
inner join sysobjects d on a.id=d.id and d.xtype='U' and d.name='E1T04_1996' where b.name ='char' AND a.length='10'
declare @sql varchar(1000)
open tb
fetch next from tb into @sql
while @@fetch_status = 0
begin
exec(@sql)
fetch next from tb INTO @sql
end
close tb
deallocate tb
--
--DECLARE @sql VARCHAR(1000)
--select @sql='alter table ['+d.name+'] alter column ['+a.name+'] nvarchar'
-- +'(100)' FROM syscolumns a
-- left join systypes b on a.xtype=b.xusertype
-- inner join sysobjects d on a.id=d.id and d.xtype='U' and d.name='E1T04_1996' where b.name ='char' AND a.length='10'
--
-- PRINT @sql
--------------------------------------------------------------------------------------
-- =======================================================
-- 批量更改某数据库中所有表中某字段的类型
-- =======================================================
IF EXISTS (
SELECT *
FROM INFORMATION_SCHEMA.ROUTINES
WHERE SPECIFIC_NAME = N'sp_AlterColumnType'
)
DROP PROCEDURE sp_AlterColumnType
GO
CREATE PROCEDURE sp_AlterColumnType
AS
-- =============================================
-- 循环当前数据库中所有用户建的表
-- =============================================
DECLARE @TableName nvarchar(100)
DECLARE @TableID nvarchar(100)
DECLARE cursor_CustomTable CURSOR FOR
SELECT [name],[ID] FROM sysobjects where type ='U'
OPEN cursor_CustomTable
FETCH NEXT FROM cursor_CustomTable INTO @TableName,@TableID
WHILE @@FETCH_STATUS = 0
BEGIN
-- =============================================
-- 循环当前表中所有列,取出列名和列的类型
-- =============================================
DECLARE @ColumnName nvarchar(100)
DECLARE @ColumnType nvarchar(100)
DECLARE cursor_Column CURSOR FOR
select [name],xtype from syscolumns where [id] = @TableID and xtype=(select xtype from systypes where name='numeric')
OPEN cursor_Column
FETCH NEXT FROM cursor_Column INTO @ColumnName,@ColumnType
WHILE @@FETCH_STATUS = 0
BEGIN
--在此处修改列类型为numeric(14,2)
exec('ALTER TABLE '+@TableName +' ALTER COLUMN '+@ColumnName +' numeric(14,2) null')
FETCH NEXT FROM cursor_Column INTO @ColumnName,@ColumnType
END
CLOSE cursor_Column
DEALLOCATE cursor_Column
-- 循环到下一个表.
FETCH NEXT FROM cursor_CustomTable INTO @TableName,@TableID
END
CLOSE cursor_CustomTable
DEALLOCATE cursor_CustomTable
GO
