查询分页的几种Sql写法

9/1/2015来源:SQL技巧人气:1252

查询分页的几种Sql写法 查询分页的几种Sql写法

摘自:http://www.cnblogs.com/zcttxs/archive/2012/04/01/2429151.html

1.创建测试环境,(插入100万条数据大概耗时5分钟)。

create database DBTestuse DBTest--创建测试表create table pagetest(id int identity(1,1) not null,col01 int null,col02 nvarchar(50) null,col03 datetime null)--1万记录集declare @i intset @i=0while(@i<10000)begin    insert into pagetest select cast(floor(rand()*10000) as int),left(newid(),10),getdate()    set @i=@i+1end

  

2.几种典型的分页sql,下面例子是每页50条,198*50=9900,取第199页数据。

--写法1,not in/topselect top 50 * from pagetest where id not in (select top 9900 id from pagetest order by id)order by id--写法2,not existsselect top 50 * from pagetest where not exists (select 1 from (select top 9900 id from pagetest order by id)a  where a.id=pagetest.id)order by id--写法3,max/topselect top 50 * from pagetestwhere id>(select max(id) from (select top 9900 id from pagetest order by id)a)order by id--写法4,row_number()select top 50 * from (select row_number()over(order by id)rownumber,* from pagetest)awhere rownumber>9900select * from (select row_number()over(order by id)rownumber,* from pagetest)awhere rownumber>9900 and rownumber<9951select * from (select row_number()over(order by id)rownumber,* from pagetest)awhere rownumber between 9901 and 9950--写法5,在csdn上一帖子看到的,row_number() 变体,不基于已有字段产生记录序号,先按条件筛选以及排好序,再在结果集上给一常量列用于产生记录序号select *from (    select row_number()over(order by tempColumn)rownumber,*    from (select top 9950 tempColumn=0,* from pagetest where 1=1 order by id)a)bwhere rownumber>9900

  

3.分别在1万,10万(取1990页),100(取19900页)记录集下测试。

测试sql:

declare @begin_date datetimedeclare @end_date datetimeselect @begin_date = getdate()<.....YOUR CODE.....>select @end_date = getdate()select datediff(ms,@begin_date,@end_date) as '毫秒'

  

1万:基本感觉不到差异。

10万:

4.结论:

1.max/top,ROW_NUMBER()都是比较不错的分页方法。相比ROW_NUMBER()只支持sql2005及以上版本,max/top有更好的可移植性,能同时适用于sql2000,access

2.not exists感觉是要比not in效率高一点点。

3.ROW_NUMBER()的3种不同写法效率看起来差不多。

4.ROW_NUMBER() 的变体基于我这个测试效率实在不好。原帖在这里http://topic.csdn.net/u/20100617/04/80d1bd99-2e1c-4083-ad87-72bf706cb536.html

PS.上面的分页排序都是基于自增字段id。测试环境还提供了int,nvarchar,datetime类型字段,也可以试试。不过对于非主键没索引的大数据量排序效率应该是很不理想的。

5.简单将ROWNUMBER,max/top的方式封装到存储过程

ROWNUMBER():

ALTER PROCEDURE [dbo].[Proc_SqlPageByRownumber](    @tbName VARCHAR(255),            --表名    @tbGetFields VARCHAR(1000)= '*',--返回字段    @OrderfldName VARCHAR(255),        --排序的字段名    @PageSize INT=20,               --页尺寸    @PageIndex INT=1,               --页码    @OrderType bit = 0,                --0升序,非0降序    @strWhere VARCHAR(1000)='',     --查询条件    --@TotalCount INT OUTPUT            --返回总记录数)AS-- =============================================-- Author:      allen (liyuxin)-- Create date: 2012-03-30-- Description: 分页存储过程(支持多表连接查询)-- Modify [1]:  2012-03-30-- =============================================BEGIN    DECLARE @strSql VARCHAR(5000)    --主语句    DECLARE @strSqlCount NVARCHAR(500)--查询记录总数主语句    DECLARE @strOrder VARCHAR(300) -- 排序类型    --------------总记录数---------------    IF ISNULL(@strWhere,'') <>''          SET @strSqlCount='Select @TotalCout=count(*) from  ' + @tbName + ' where 1=1 '+ @strWhere    ELSE SET @strSqlCount='Select @TotalCout=count(*) from  ' + @tbName        --exec sp_executesql @strSqlCount,N'@TotalCout int output',@TotalCount output    --------------分页------------    IF @PageIndex <= 0 SET @PageIndex = 1    IF(@OrderType<>0) SET @strOrder=' ORDER BY '+@OrderfldName+' DESC '    ELSE SET @strOrder=' ORDER BY '+@OrderfldName+' ASC '    SET @strSql='SELECT * FROM     (SELECT ROW_NUMBER() OVER('+@strOrder+') RowNo,'+ @tbGetFields+' FROM ' + @tbName + ' WHERE 1=1 ' + @strWhere+' ) tb     WHERE tb.RowNo BETWEEN '+str((@PageIndex-1)*@PageSize+1)+' AND ' +str(@PageIndex*@PageSize)    exec(@strSql)    SELECT @TotalCountEND复制代码
public static SqlParameter MakeInParam(string ParamName, SqlDbType DbType, Int32 Size, object Value)        {            return MakeParam(ParamName, DbType,Size, ParameterDirection.Input, Value);        }        public static SqlParameter MakeOutParam(string ParamName, SqlDbType DbType)        {            return MakeParam(ParamName, DbType, 0, ParameterDirection.Output, null);        }        public static SqlParameter MakeParam(string ParamName, SqlDbType DbType, Int32 Size, ParameterDirection Direction, object Value)        {            SqlParameter param;            if (Size > 0)                param = new SqlParameter(ParamName, DbType, Size);            else                param = new SqlParameter(ParamName, DbType);            param.Direction = Direction;            if (!(Direction == ParameterDirection.Output && Value == null))                param.Value = Value;            return param;        }        /// <summary>        /// 分页获取数据列表及总行数        /// </summary>        /// <param name="tbName">表名</param>        /// <param name="tbGetFields">返回字段</param>        /// <param name="OrderFldName">排序的字段名</param>        /// <param name="PageSize">页尺寸</param>        /// <param name="PageIndex">页码</param>        /// <param name="OrderType">false升序,true降序</param>        /// <param name="strWhere">查询条件</param>        public static DataSet GetPageList(string tbName, string tbGetFields, string OrderFldName, int PageSize, int PageIndex, string strWhere)        {            SqlParameter[] parameters = {                        MakeInParam("@tbName",SqlDbType.VarChar,255,tbName),                        MakeInParam("@tbGetFields",SqlDbType.VarChar,1000,tbGetFields),                         MakeInParam("@OrderfldName",SqlDbType.VarChar,255,OrderFldName),                         MakeInParam("@PageSize",SqlDbType.Int,0,PageSize),                         MakeInParam("@PageIndex",SqlDbType.Int,0,PageIndex),                         MakeInParam("@OrderType",SqlDbType.Bit,0,OrderType),                         MakeInParam("@strWhere",SqlDbType.VarChar,1000,strWhere),                        // MakeOutParam("@TotalCount",SqlDbType.Int)                        };            return RunProcedure("Proc_SqlPageByRownumber", parameters, "ds");        }       复制代码
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调用:

public DataTable GetList(string tbName, string tbGetFields, string OrderFldName, int PageSize, int PageIndex, string strWhere, ref int TotalCount)        {            DataSet ds = dal.GetList(tbName, tbGetFields, OrderFldName, PageSize, PageIndex,  strWhere);            TotalCount = Convert.ToInt32(ds.Tables[1].Rows[0][0]);            return ds.Tables[0];        }复制代码
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注意:多表连接时需注意的地方1.必填项:tbName,OrderfldName,tbGetFields2.实例:tbName =“UserInfo u INNER JOIN Department d ON u.DepID=d.ID” tbGetFields=“u.ID AS UserID,u.Name,u.Sex,d.ID AS DepID,d.DefName” OrderfldName=“u.ID,ASC|u.Name,DESC” (格式:Name,ASC|ID,DESC) strWhere:每个条件前必须添加 AND (例如:AND UserInfo.DepID=1 )

Max/top:(简单写了下,需要满足主键字段名称就是"id")