存储过程中如何执行带输出参数的动态SQL

5/6/2008来源:SQL技巧人气:13541

SQL Server存储过程中执行带输出参数的动态sql是很多人经常碰到的问题,比如根据一些条件查询列表,并返回记录数等。下面是一个参考示例,查询用户列表,它可以利用临时表实现翻页,并带有死锁和超时检测功能。

CREATE PRocedure pUserList

(

@UserType char(2),

@pagenum int,

@perpagesize int,

@pagetotal int out,

@rowcount int out

)

as

set nocount on

DECLARE @Err INT,@ErrCounter INT

declare @sql nvarchar(2000) --声明动态sql执行语句

declare @pagecount int --当前页数

declare @sWhere nvarchar(200)

declare @sOrder nvarchar(100)

set @sWhere = ' where 1=1 '

if not(@UserType is null)

set @sWhere = @sWhere + ' and UserType = ' + @UserType

set @sOrder = ' order by UserID '

--取得当前数据库的记录总数

declare @row_num int

LockTimeOutRetry:

--创建临时表,作为数据过滤

create table #change (T_id int)

set @sql = 'select @row_num=count(*) from dbo.[User]' + @sWhere

exec sp_executesql @sql,N'@row_num int output', @row_num output

if @row_num % @perpagesize =0

set @pagetotal = @row_num/@perpagesize

else

set @pagetotal = @row_num/@perpagesize + 1

set @rowcount = @row_num

if @row_num > @perpagesize

begin

set @row_num = @pagenum * @perpagesize

if @row_num = @perpagesize

begin

set @sql = N'select top ' + cast(@perpagesize as varchar)

+ ' UserID,LoginName,RealName from dbo.[User]' + @sWhere + @sOrder

exec sp_executesql @sql

SET @Err = @@ERROR

IF @Err <> 0 GOTO ErrorHandler

return 0

end

else

begin

set @row_num = (@pagenum-1) * @perpagesize

set @pagecount = @row_num

set @sql=N'insert #change (T_id) select top '

+ cast(@pagecount as varchar) + ' UserID from dbo.

[User] '+@sWhere+' and UserID not in (select T_id from #change)' + @sOrder

exec sp_executesql @sql

set @sql = N'select top ' + cast(@perpagesize as varchar) + ' UserID,LoginName,RealName from dbo.[User] '+@sWhere+' and UserID not in (select T_id from #change)' + @sOrder

exec sp_executesql @sql

SET @Err = @@ERROR

IF @Err <> 0 GOTO ErrorHandler

return 0

end

end

else

begin

set @sql = 'select UserID,LoginName,RealName

from dbo.[User]' + @sWhere + @sOrder

exec sp_executesql @sql

SET @Err = @@ERROR

IF @Err <> 0 GOTO ErrorHandler

return 0

end

ErrorHandler:

IF (@Err = 1222 OR @Err = 1205) AND @ErrCounter = 5

BEGIN

RAISERROR ('Unable to Lock Data after five attempts.', 16,1)

return -100

END

IF @Err = 1222 OR @Err = 1205 -- Lock Timeout / Deadlock

BEGIN

WAITFOR DELAY '00:00:00.25'

SET @ErrCounter = @ErrCounter + 1

GOTO LockTimeOutRetry

END

-- else unknown error

RAISERROR (@err, 16,1) WITH LOG

return -100

GO

SET QUOTED_IDENTIFIER OFF

GO

SET ANSI_NULLS ON

GO

SET QUOTED_IDENTIFIER ON

GO

SET ANSI_NULLS ON

GO