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语句和存储过程 查询语句的流程控制
将表数据生成SQL脚本的存储过程
SQL Server 2005 常见问题解答
在SQL2005 轻松配置SSIS包
SQL Server 服务器安装剖析
SQL Server数据库检修
用户自定义的数据库修复
如何修复SQLSERVER 数据库置疑之
SQL中与IP相关的常见问题
动态SQL语句
从SQL中的一个表中导出HTML文件表格
在SQL中删除重复记录(多种方法)
SQLServer和Oracle常用函数对比
删除全文索引
复制表结构的通用存储过程
取汉字拼音首字母的存储过程
SQL Server中格式化表中的数据
SQL SERVER的命名规则
SQL server锁的机制
用脚本缩小数据库日志

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: 85 ::
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