SQL ServerOptimizing SQL Server Query PerformanceMaciej PileckiAt a Glance:Analyzing execution plans Optimizing queries Identifying queries to tuneWhen optimizing your database server, you need to tune the performance of individual queries. This is as important as—perhaps even more important than—tunin...
(以上的图来自网络:Understanding how SQL Server executes a query) 还是从问题出发,能问出问题的多少,反映了自己知道的层次,更能翻出自己自己薄弱的地方。 如果有明白的地方,可以参考这篇文章,写得很详细:Understanding how SQL Server executes a query 1 客户端,在 SQL Server 看来有两个概念,一个是 connecti...
SQL Server Query Store is a performance monitoring tool that helps us evaluate the performance of a SQL query in terms of several different performance metrics such as CPU and Memory Consumption, execution time and the I/O cycles consumed by the query. Query store is similar to the windows “...
貌似上面一种情况是针对oracle优化器的,sql server优化器还没那么智能可以识别出这种参数探嗅的模式,只能对语句一模一样的SQL进行软解析。这里有特殊,除非是明显不会影响查询计划的参数化,比如用主键来做等于限制,无论怎么样都是做cluster index seek,所以SQL SERVER优化器就自动参数化了。 select * from dbo.dimst...
The test database is Microsoft SQL Server 2008r2 running inside a Window 7 VM with a 4 CPU cores, 6GB of RAM, and the PAE extensions on. The disk image is on 7200 RPM spinning media. In my testing there seemed always to be free memory so I think that is not a limiting factor. ...
最佳化 SQL Server 預存程序以避免重新編譯 (sql-server-performance.com/rd_optimizing_sp_recompiles.asp) SQL Server 2000 中的查詢重新編譯 (msdn2.microsoft.com/aa902682.aspx)還有一個提供豐富資訊的好地方,就是 SQL Server 2005 動態管理檢視 (DMV)。當 CPU 使用率很高時,我會使用幾個 DMV 來協助我...
An expression that does not use SARG operators does not improve performance, because the SQL Server Compact Edition query processor has to evaluate every row to determine whether it meets the filter clause. Therefore, an index is not useful on expressions that do not use SARG operators. Non-...
(The article onQuery Process Overview and Performance Tuning approaches for SQL Server CE 2.0covers the same points as above, but I found it better than the MSDN links J. It is relevant for SQL Server Compact 3.5 too.) Now here are some additional ways you can improve performance: ...
How to analyze query performance characteristics in SQL Server Best practices The more filters in the Where clause the better. Simply because the more filters we put in is less data that SQL Server will return. You’ve seen this in this article, but keep in mind when you see scans; you ...
Once the .sqlplan file has been saved, opening this file in SQL Server Enterprise Manager provides one with a graphical interpretation of the executed query. This enables one to easily analyse the actual query execution plan.The other useful, but similar query, is the one to analyse IO bas...