当前位置: 首页 > 图文教程 > 数据库 > MSSQL > SQL优化实例:从运行30分钟到运行只要30秒

MSSQL
SQL Server 2008批量删除及插入的方法
SQL Server 2008对T-SQL语言的增强
SQL Server 2008中不推荐及不支持的功能
跟我学SQL:(七)从子表里删除数据
如何使用 SQL Server 数据库查询累计值
如何使用SQL Server数据库查询累计值
选择是否恢复整个SQL Server的方法介绍
sql server注册表操作相关的几个未公开过程
在SQL Server中通过.NET远程的执行SQL文件
讲解SQL Server数据库被挂马的解决方案
SQL Server COALESCE()函数的创新应用
教你快速确定SQL Server栏中的最大值
避免在 PL/SQL 中使用嵌套游标查询
轻松掌握SQL Sever中各种语句的完整语法
Asp.net编程中的数组基础实例学习
SQL Server 2005最后升级:SP3年底发布
SQL Server 2008数据库中的新数据类型
SQL Server不允许进行远程连接的解决办法
SQLServer2005 XML在T-SQL中的应用
使用SQL Server代理运行CmdExec命令

MSSQL 中的 SQL优化实例:从运行30分钟到运行只要30秒


出处:互联网   整理: 软晨网(RuanChen.com)   发布: 2009-10-30   浏览: 133 ::
收藏到网摘: n/a

 以下的SQL语句在服务器需要运行长达30分钟才能完成:
SELECT     dbo.ComFlow.ComFlowCode, dbo.ComFlow.ComCode, dbo.ComFlow.CustCode, dbo.ComFlow.DepartCode, dbo.ComFlow.SaleCode,
                      dbo.ComFlow.EmpCode, dbo.ComFlow.Quantity * dbo.Commodity.ConvertRate AS Quantity, CONVERT(datetime, DATENAME(yyyy,
                      dbo.ComFlow.FlowDate) + '-' + DATENAME(mm, dbo.ComFlow.FlowDate) + '-' + DATENAME(dd, dbo.ComFlow.FlowDate)) AS FlowDate,
                      dbo.ComFlow.SalType, dbo.Employee.DepartCode AS DepartIn, dbo.Sale.DepartCode AS DepartOut,
                      dbo.ComFlow.Quantity * dbo.Commodity.TradePrice * dbo.Commodity.Discount / 100 AS Total, dbo.Department.GrpCode AS GrpCodeIn,
                      Department1.GrpCode AS GrpCodeOut
FROM         dbo.ComFlow INNER JOIN
                      dbo.Customer ON
                dbo.ComFlow.SalType IN (N'促销', N'流向退货', N'多级流向') AND dbo.ComFlow.CustCode = dbo.Customer.CustCode
                Or ComFlow_1.SalType IN (N'自然流向', N'自然流向退货') AND ComFlow_1.OutCustCode = Customer_1.CustCode
            INNER JOIN
                      dbo.CustomerRelation ON dbo.ComFlow.ComCode = dbo.CustomerRelation.ComCode AND
                      dbo.CustomerRelation.CustCode = dbo.Customer.CustCode INNER JOIN
                      dbo.Employee ON dbo.CustomerRelation.EmpCode = dbo.Employee.EmpCode INNER JOIN
                      dbo.Sale ON dbo.ComFlow.SaleCode = dbo.Sale.SaleCode INNER JOIN
                      dbo.Department ON dbo.Department.DepartCode = dbo.Employee.DepartCode INNER JOIN
                      dbo.Department AS Department1 ON Department1.DepartCode = dbo.Sale.DepartCode AND
                      dbo.Department.GrpCode <> Department1.GrpCode INNER JOIN
                      dbo.Commodity ON dbo.ComFlow.ComCode = dbo.Commodity.ComCode
WHERE     (NOT (dbo.ComFlow.SalType = N'流向退货')) OR
                      (NOT (dbo.Customer.Type = N'医药公司'))
虽然说,我们使用这个语句的应用是一个BI应用,实时性要求不高,但是,我觉得没有道理会运行这么久,应该有办法优