如何同时对多个表或列操作
通过使用这个存储过程,你就可以方便的对数据库中具有一定规则的或者全部表,对这里的字段进行各种操作,具体看示例!
CREATE PROCEDURE SP_execSQLonDB
(@TABLENAME VARCHAR(50), --表名条件
@COLUMNNAME VARCHAR(50), --字段条件
@SQL NVARCHAR(4000), --执行的SQL
@INCLUDE_NTI CHAR(1) = 'N') --是否包含Text,NText,Image数据类型
AS
BEGIN
--Variable Declaration
--变量定义
DECLARE @strSQL NVARCHAR(4000)
DECLARE @SQL2 NVARCHAR(4000)
DECLARE @sTableName VARCHAR(200)
DECLARE @sColumnName VARCHAR(200)
DECLARE @SQLTemp NVARCHAR(4000)
--Check whether to include TEXT, NTEXT, IMAGE data types
--检查是否需要包含 Text,NText,Image数据类型
SET @INCLUDE_NTI = UPPER(LTRIM(RTRIM(@INCLUDE_NTI)))
IF @INCLUDE_NTI NOT IN ('N', 'Y')
SET @INCLUDE_NTI = 'N'
--Construct a cursor to get the list of Table/Column Names aclearcase/" target="_blank" >ccording to the @TABLENAME and @COLUMNNAME parameters.
--创建一个游标来读取表名和列名的列表,这里列表由参数@TABLENAME 和 @COLUMNNAME 决定
SET @strSQL = N'DECLARE TabColCursor CURSOR FOR SELECT RTRIM(LTRIM(SU.name)) + '.' + LTRIM(RTRIM(SO.name)), SC.name FROM sysobjects SO INNER JOIN syscolumns SC ON SO.id = SC.id INNER JOIN sysusers SU ON SO.uid = SU.uid WHERE SO.xtype = 'U' '
--Filter out Text/NText/Image data types if it is not included
--假如不包含Text/NText/Image数据类型,把他们过滤掉
IF @INCLUDE_NTI = 'N'
--In SysColumns sytem table XTYPE column corresponds to Column Data Type
SET @strSQL = @strSQL + ' AND SC.xtype NOT IN (35, 99, 34) '
--Add the TABLE(S) name i.e. filter if it is supplied
--假如有提供表名参数,把它写入过滤条件中
IF @TABLENAME IS NOT NULL AND ltrim(rtrim(@TABLENAME)) <> '
BEGIN
SET @TABLENAME = REPLACE(@TABLENAME, ', ', ',')
SET @strSQL = @strSQL + ' AND (SO.name LIKE '' + REPLACE(@TABLENAME, ',', '' OR SO.name LIKE '') + '')'
SET @SQLTemp= ' AND (SO.name LIKE '' + REPLACE(@TABLENAME, ',', '' OR SO.name LIKE '') + '')'
END
--Add the COLUMN(S) name i.e. filter if it is supplied
--假如有提供列名参数,把它写入过滤条件中
IF @COLUMNNAME IS NOT NULL AND ltrim(rtrim(@COLUMNNAME)) <> '
BEGIN
SET @COLUMNNAME = REPLACE(@COLUMNNAME, ', ', ',')
SET @strSQL = @strSQL + ' AND (SC.name LIKE '' + REPLACE(@COLUMNNAME, ',', '' OR SC.name LIKE '') + '')'
END
--Execute the constructed "Cursor Declaration" string
--执行定义游标的SQL语句
EXECUTE sp_executesql @strSQL
IF @@ERROR > 0
BEGIN
PRINT 'Error while declaring the Cursor. Please check out the parameters supplied to the Procedure'
RETURN -1
END
--Database Transaction.
--标记一个显式本地事务的起始点
BEGIN TRANSACTION gDatabaseTrans
--Open the cursor
--打开游标
OPEN TabColCursor
--Fetch te Table, Column names to variables
--用游标取出标名、列名对应到参数
FETCH NEXT FROM TabColCursor
INTO @sTableName, @sColumnName
--Execute the SQL statement supplied in @SQL parameter on every row of Cursor's data
--对于每一行游标取出的数据,执行由@SQL参数传进来的SQL语句
WHILE @@FETCH_STATUS = 0
BEGIN
--Construct SQL2 to Execute supplied @SQL
--by replacing @TABLENAME, @COLUMNNAME with running Table Name, Column Name of Cursor's data
--用游标取出的表名列名来替换@SQL中的@TABLENAME, @COLUMNNAME来构造SQL2
SET @SQL2 = @SQL
SET @SQL2 = REPLACE(@SQL2, '@TABLENAME', @sTableName)
SET @SQL2 = REPLACE(@SQL2, '@COLUMNNAME', @sColumnName)
--Execute the constructed SQL2
--执行SQL2
EXECUTE sp_executesql @SQL2
--Check for errors
--检查错误
IF @@ERROR <> 0
BEGIN
--On Error, Destroy objects, Rollback transaction
--Return -1 as UNSUCCESSFUL flag
--如果发生错误,删除游标,回滚
--返回错误标记 -1
PRINT 'Error occurred'
DEALLOCATE TabColCursor
ROLLBACK TRANSACTION gDatabaseTrans
RETURN -1
END
--Process Next Row of Cursor
--进行下一行数据
FETCH NEXT FROM TabColCursor
INTO @sTableName,@sColumnName
END
--Destroy CURSOR object
--删除游标
DEALLOCATE TabColCursor
--Procedure executed properly. Commit the Transaction.
--Return 0 as SUCCESSFUL flag
--成功完成存储过程,成功结束事务
--返回成功标记 0
COMMIT TRANSACTION gDatabaseTrans
RETURN 0
END
使用例子
1、这个例子在NORTHWIND数据库上执行
把所有表中列名包含Name的列中,把以“Ltd.”结尾的列替换成“LIMITED”。
用 SELECT * FROM Suppliers检查运行结果!
EXEC SP_execSQLonDB
', --没有表名条件,针对所有表
'%Name%', --列名条件,列名包含“Name”字符串
'UPDATE @TABLENAME SET @COLUMNNAME = REPLACE(@COLUMNNAME,'Ltd.','LIMITED')
WHERE @COLUMNNAME LIKE '%Ltd.'', --UPDATE 语句
'N' --不包含NTEXT,TEXT,IMAGE数据类型
2、这个例子也在NORTHWIND数据库上执行
统计所有表中列名包含Name的列的值是“QUICK-Stop”的数量
create table ##TMP1 (table_name varchar(200),column_name varchar(200),rou_count int)
exec SP_execSQLonDB
',
'%Name%',
'DECLARE @iCount as int
SELECT @iCount=COUNT(1) FROM @TABLENAME WHERE @COLUMNNAME = 'QUICK-Stop'
IF @iCount >0
INSERT INTO ##TMP1 SELECT '@TABLENAME','@COLUMNNAME',@iCount',
'N'
select * from ##TMP1
3、这个例子自己理解
针对所有以“EMPLOYEE”开头的表,以“DEPT”开头的字段执行存储过程。
EXEC SP_execSQLonDB
'EMPLOYEE%',
'DEPT%',
'EXEC USP_DeptStates '@TABLENAME','@COLUMNNAME'',
'N'
4、还是自己理解
对@TABLENAME @COLUMNNAME参数给于多个值!
EXEC SP_execSQLonDB
'EMPLOYEE%,PF%',
'SALARY,%AMOUNT%',
'EXEC USP_EMPLOYEE_PF ',
'N'