mssql 分页存储过程 - 使用Top

mssql分页store procedure-使用Top

USE DBS_REG_2012
GO
/****** Object: StoredProcedure [dbo].[SP_GetPage] Script Date: 08/01/2012 13:52:23 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO

ALTER PROC [dbo].[SP_GetPage]
(
@tbname nvarchar(100), --要分页显示的表名
@FieldKey nvarchar(1000), --用于定位记录的主键(惟一键)字段,可以是逗号分隔的多个字段
@PageCurrent int=1, --要显示的页码
@PageSize int=20, --每页的大小(记录数)
@FieldShow nvarchar(1000)='', --以逗号分隔的要显示的字段列表,如果不指定,则显示所有字段
@FieldOrder nvarchar(1000)='', --以逗号分隔的排序字段列表,可以指定在字段后面指定DESC/ASC
@WhereString nvarchar(1000)=N'', --查询条件
@RecordCount int OUTPUT --总记录数
)
AS
SET NOCOUNT ON

--检查对象是否有效
IF OBJECT_ID(@tbname) IS NULL
BEGIN
RAISERROR(N'The ojbect "%s" not exists.',1,16,@tbname)
RETURN
END
IF OBJECTPROPERTY(OBJECT_ID(@tbname),N'IsTable')=0
AND OBJECTPROPERTY(OBJECT_ID(@tbname),N'IsView')=0
AND OBJECTPROPERTY(OBJECT_ID(@tbname),N'IsTableFunction')=0
BEGIN
RAISERROR(N'"%s" not table, views or table values function.',1,16,@tbname)
RETURN
END

--分页字段检查
IF ISNULL(@FieldKey,N'')=''
BEGIN
RAISERROR(N'Paging processing need primary key (or the unique key).',1,16)
RETURN
END

--其他参数检查及规范
IF ISNULL(@PageCurrent,0)<1 SET @PageCurrent=1
IF ISNULL(@PageSize,0)<1 SET @PageSize=20
IF ISNULL(@FieldShow,N'')=N'' SET @FieldShow=N'*'
IF ISNULL(@FieldOrder,N'')=N''
SET @FieldOrder=N''
ELSE
SET @FieldOrder=N'ORDER BY '+LTRIM(@FieldOrder)
IF ISNULL(@WhereString,N'')=N''
SET @WhereString=N''
ELSE
SET @WhereString=N'WHERE ('+@WhereString+N')'

--如果@RecordCount为NULL值,则计算总页数(这样设计可以只在第一次计算总页数,以后调用时,把总页数传回给存储过程,避免再次计算总页数,对于不想计算总页数的处理而言,可以给@RecordCount赋值)
IF @RecordCount IS NULL
BEGIN
DECLARE @sql nvarchar(4000)
SET @sql=N'SELECT @RecordCount=COUNT(*)'
+N' FROM '+@tbname
+N' '+@WhereString
EXEC sp_executesql @sql,N'@RecordCount int OUTPUT',@RecordCount OUTPUT
END

--计算分页显示的TOPN值
DECLARE @TopN varchar(20),@TopN1 varchar(20)
SELECT @TopN=@PageSize,
@TopN1=(@PageCurrent-1)*@PageSize

--第一页直接显示
IF @PageCurrent=1
EXEC(N'SELECT TOP '+@TopN
+N' '+@FieldShow
+N' FROM '+@tbname
+N' '+@WhereString
+N' '+@FieldOrder)
ELSE
BEGIN
--处理别名
IF @FieldShow=N'*'
SET @FieldShow=N'a.*'

--生成主键(惟一键)处理条件
DECLARE @Where1 nvarchar(4000),@Where2 nvarchar(4000),
@s nvarchar(1000),@Field sysname
SELECT @Where1=N'',@Where2=N'',@s=@FieldKey
WHILE CHARINDEX(N',',@s)>0
SELECT @Field=LEFT(@s,CHARINDEX(N',',@s)-1),
@s=STUFF(@s,1,CHARINDEX(N',',@s),N''),
@Where1=@Where1+N' AND a.'+@Field+N'=b.'+@Field,
@Where2=@Where2+N' AND b.'+@Field+N' IS NULL',
--@WhereString=REPLACE(@WhereString,@Field,N'a.'+@Field),
--@FieldOrder=REPLACE(@FieldOrder,@Field,N'a.'+@Field),
@FieldShow=REPLACE(@FieldShow,@Field,N'a.'+@Field)
SELECT --@WhereString=REPLACE(@WhereString,@s,N'a.'+@s),
--@FieldOrder=REPLACE(@FieldOrder,@s,N'a.'+@s),
@FieldShow=REPLACE(@FieldShow,@s,N'a.'+@s),
@Where1=STUFF(@Where1+N' AND a.'+@s+N'=b.'+@s,1,5,N''),
@Where2=CASE
WHEN @WhereString='' THEN N'WHERE ('
ELSE @WhereString+N' AND ('
END+N'b.'+@s+N' IS NULL'+@Where2+N')'

print (N'SELECT TOP '+@TopN
+N' '+@FieldShow
+N' FROM '+@tbname
+N' a LEFT JOIN(SELECT TOP '+@TopN1
+N' '+@FieldKey
+N' FROM '+@tbname
+N' a '+@WhereString
+N' '+@FieldOrder
+N')b ON '+@Where1
+N' '+@Where2
+N' '+@FieldOrder)
--执行查询
EXEC(N'SELECT TOP '+@TopN
+N' '+@FieldShow
+N' FROM '+@tbname
+N' a LEFT JOIN(SELECT TOP '+@TopN1
+N' '+@FieldKey
+N' FROM '+@tbname
+N' a '+@WhereString
+N' '+@FieldOrder
+N')b ON '+@Where1
+N' '+@Where2
+N' '+@FieldOrder)
END