SQL order by ID desc/asc加一个排序的字段解决查询建
导读:1建站知识解决方法就是在order by ID desc再加一个排序的字段,这样子可能会把速度提高很多,需要朋友可以试一下网站seo优化课程网站推广优化seo。
解决方法就是在order by ID desc再加一个排序的字段,这样子可能会把速网站seo优化课程度提高很多。再加止排序的字段因查询而异了 如表
复制代码 代码如下:
CREATE TABLE [dbo].[CMPP_SendCentre] ( [id] [int] IDENTITY (1, 1) NOT NULL , [SendType] [v网站seo优化archar] (10) COLLATE Chinese_PRC_CI_AS NOT NULL , [SendDate] [datetime] NOT NULL , [Port] [varchar] (50) COLLATE Chinese_PRC_CI_AS NOT NULL , [Service_ID] [varchar] (20) COLLATE Chinese_PRC_CI_AS NOT NULL , [FeeType] [varchar] (2) COLLATE Chinese_PR网站seo优化软件C_CI_AS NOT NULL , [FeeCode] [varchar] (6) COLLATE Chinese_PRC_CI_AS NOT NULL , [Msg_Content] [varchar] (1024) COLLATE Chinese_PRC_CI_AS NOT NULL , [SendCount] [int] NOT NULL , [SucceedCount] [int] NOT NULL ) ON [PRIMARY] GO CREATE TABLE [dbo].[CMPP_SendCentreMo] ( [id] [int] IDENTITY (1, 1) NOT NULL , [SendCentreID] [int] NOT NULL , [Mo] [varchar] (20) COLLATE Chinese_PRC_CI_AS NOT NULL , [Stat] [varchar] (10) COLLATE Chinese_PRC_CI_AS NULL ) ON [PRIMARY] GO CMPP_SendCentreMo.SendCentreID 与CMPP_SendCentre.ID成外建关系
于是建了一个视图复制代码 代码如下:
CREATE VIEW dbo.ViewCMPP_SendCentreMo AS SELECT dbo.CMPP_SendCentreMo.id, dbo.CMPP_SendCentreMo.SendCentreID, dbo.CMPP_SendCentreMo.Mo, dbo.CMPP_SendCentreMo.Stat, dbo.CMPP_SendCentre.SendType, dbo.CMPP_SendCentre.SendDate, dbo.CMPP_SendCentre.Port, dbo.CMPP_SendCentre.Service_ID, case dbo.CMPP_SendCentre.FeeType when '01' then '免费' when '02' then '点播' else '包月' end as FeeType, cast(dbo.CMPP_SendCentre.FeeCode as smallint) as FeeCode, dbo.CMPP_SendCentre.Msg_Content FROM dbo.CMPP_SendCentre INNER JOIN dbo.CMPP_SendCentreMo ON dbo.CMPP_SendCentre.id = dbo.CMPP_SendCentreMo.SendCentreID
一开始的查询语句为复制代码 代码如下:
select top 6*from [ViewCMPP_SendCentreMo] where SendType = '扣费' order by id desc
发现非常的慢 经过了解,原因是order by id desc/asc的查询是一行一行的找数据,所以非常的慢 于是改成了复制代码 代码如下:
select top 6*from [ViewCMPP_SendCentreMo] where SendType = '扣费' order by SendCentreID desc, id desc
查询就非常的快了相关网站seo优化课程网站推广优化seo。声明: 本文由我的SEOUC技术文章主页发布于:2023-05-23 ,文章SQL order by ID desc/asc加一个排序的字段解决查询建主要讲述字段,标签,SQL网站建设源码以及服务器配置搭建相关技术文章。转载请保留链接: https://www.seouc.com/article/web_6114.html