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分页存储过程,综合了NOT_IN和SET ROWCOUNT

2014年02月12日 ⁄ 综合 ⁄ 共 4122字 ⁄ 字号 评论关闭

分页存储过程,自己把“NOT_IN”和“SET ROWCOUNT”两种方式综合了一下。
“SET ROWCOUNT”算法不变,“NOT_IN”排序时加了主键字段,这样速度提升了很多而且结果是单向唯一的,但不是双向可逆的。“SET ROWCOUNT”没有速度问题,“NOT_IN”排序加了主键字段后在30W记录时对非索引字段、非聚合字段的排序翻一页不过3秒钟,还可以吧:P
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CREATE PROCEDURE Paging_Custom
(
@Tables varchar(1000),
@PK varchar(100),
@Sort varchar(200) = NULL,
@isAscending bit=1,
@PageNumber int = 1,
@PageSize int = 10,
@Fields varchar(1000) = '*',
@Filter varchar(1000) = NULL,
@Group varchar(1000) = NULL)
AS

DECLARE @strFilter varchar(1000)
DECLARE @strSimpleFilter varchar(1000)
DECLARE @strGroup varchar(1000)

DECLARE @SortTable varchar(100)
DECLARE @SortName varchar(100)
DECLARE @strPKColumn varchar(100)

DECLARE @strSortColumn varchar(200)
DECLARE @operator char(2)

/*Set filter & group variables.*/
IF @Filter IS NOT NULL AND @Filter != ''
BEGIN
   SET @strFilter = ' WHERE ' + @Filter + ' '
   SET @strSimpleFilter = ' AND ' + @Filter + ' '
END
ELSE
BEGIN
   SET @strSimpleFilter = ' '
   SET @strFilter = ' '
END
IF @Group IS NOT NULL AND @Group != ''
SET @strGroup = ' GROUP BY ' + @Group + ' '
ELSE
begin
SET @strGroup = ' '
end

/*count*/
exec ('select count(*) from ' +@Tables+' '+ @strFilter)

/*operator and asc_desc*/
declare @strAsc_Des varchar(10)
IF @isAscending = 0
BEGIN  
   SET @operator = '<='
   SET @strAsc_Des = ' Desc '
END
ELSE
BEGIN
   SET @operator = '>='
   SET @strAsc_Des = ' ASC '
END

/*Set sorting variables.*/
/*Default Sorting*/
IF @Sort IS NULL OR   @Sort= ''
BEGIN
SET @Sort = @PK
END

SET @strSortColumn = @Sort

IF CHARINDEX('.', @PK) > 0
BEGIN
   SET @strPKColumn = SUBSTRING(@PK, CHARINDEX('.',@PK) + 1, LEN(@PK))
END
ELSE
BEGIN
   SET @strPKColumn = @PK  
END
IF CHARINDEX('.', @strSortColumn) > 0
BEGIN
   SET @SortTable = SUBSTRING(@strSortColumn, 0, CHARINDEX('.',@strSortColumn))
   SET @SortName = SUBSTRING(@strSortColumn, CHARINDEX('.',@strSortColumn) + 1, LEN(@strSortColumn))
END
ELSE
BEGIN
   SET @SortTable = @Tables
   SET @SortName = @strSortColumn
END

/*Handle complex table*/
--Be join table,so get the left table
IF CHARINDEX(' join ',@Tables) > 0
BEGIN
SET @SortTable=SUBSTRING(ltrim(@Tables),0,CHARINDEX(' ',@Tables))
SET @strSortColumn = @SortTable+'.'+@SortName
END

/*Check the sortColumn if be Unique*/

IF @SortName <> @strPKColumn
BEGIN
DECLARE @tempName varchar(100)

SELECT @tempName=b.name
FROM sysobjects a INNER JOIN
       sysobjects b ON a.id = b.parent_obj
     INNER JOIN sysindexes c ON b.name = c.name INNER JOIN
       sysindexkeys d ON c.id = d.id AND c.indid = d.indid INNER JOIN
       syscolumns e ON d.id = e.id AND d.colid = e.colid
WHERE (b.xtype = 'UQ') AND (a.name = @SortTable) AND (e.name = @SortName)

IF @tempName IS NULL
BEGIN

GOTO Paging_Not_In

END
END

Paging_RowCount:

/*Find the @SORT type*/

DECLARE @type varchar(100)
DECLARE @prec int

SELECT @type=t.name, @prec=c.prec
FROM sysobjects o
JOIN syscolumns c on o.id=c.id
JOIN systypes t on c.xusertype=t.xusertype
WHERE o.name = @SortTable AND c.name = @SortName

IF CHARINDEX('char', @type) > 0
    SET @type = @type + '(' + CAST(@prec AS varchar) + ')'

DECLARE @strPageSize varchar(50)
DECLARE @strStartRow varchar(50)

/*Default Page Number*/
--IF @PageNumber < 1
--SET @PageNumber = 1

/*Set paging variables.*/
SET @strPageSize = CAST(@PageSize AS varchar(50))
SET @strStartRow = CAST(((@PageNumber - 1)*@PageSize + 1) AS varchar(50))

/*Execute dynamic query*/

EXEC('DECLARE @SortColumn ' + @type + '
SET ROWCOUNT ' + @strStartRow +
' SELECT @SortColumn=' + @strSortColumn + ' FROM ' + @Tables + @strFilter + ' ' + @strGroup +
' ORDER BY ' + @Sort + @strAsc_Des+'SET ROWCOUNT ' + @strPageSize +
'SELECT ' + @Fields + ' FROM ' + @Tables + ' WHERE ' + @strSortColumn + @operator + ' @SortColumn ' +
@strSimpleFilter + ' ' + @strGroup + ' ORDER BY ' + @Sort + @strAsc_Des )
RETURN

Paging_Not_In:

DECLARE @strTotalNum int
SET @strTotalNum = (@PageNumber - 1)*@PageSize

--如果排序是索引列则notin方法会非常缓慢
--下限以10000为界
--if (@strTotalNum > 10000)
--begin
--declare @TotalCount int
--declare @SQL nvarchar(100)

--set @SQL = 'select @TotalCount = count(*) from ' +@Tables+' '+ @strFilter
--exec sp_executesql @SQL,N'@TotalCount int output',@TotalCount out
--上限以3/4为界
--if (@strTotalNum/@TotalCount < 0.75) goto Paging_ASCD_ESC
--end

--第一页
IF   @strTotalNum = 0
begin
exec('select top '+@PageSize+' '+@Fields+' from '+@Tables+' '+@strFilter+ @strGroup + ' ORDER BY ' + @Sort + @strAsc_Des+ ','+ @PK + @strAsc_Des)  
end
ELSE
begin
exec('select top '+@PageSize+' '+@Fields+' from '+@Tables+'   where '
+@PK+' not in(select top '
+@strTotalNum+' '+@PK+' from '+@Tables+' '+@strFilter+ @strGroup +
' ORDER BY ' + @Sort + @strAsc_Des + ','+ @PK + @strAsc_Des
+') '+@strSimpleFilter+ @strGroup + ' ORDER BY ' + @Sort + @strAsc_Des + ','+ @PK + @strAsc_Des)
end
RETURN
Paging_ASCD_ESC:

GO

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