steps to optimize sql query

Label:Planning Cache (plan caches) If SQL Server has found a good way to execute a piece of code, it should be reused as a subsequent request because Generating execution plans is time-consuming and resource-intensive, There is a point in doing so. If the cached plan is not found, then command Parser generates a query tree on the T-SQL basis. The internal struct

size of the data buffer, the server's busyness, and whether the data required to complete the query is in the data buffer or on the disk, the only data we can control is the number of logical reads required to obtain the query results. Therefore, in the query performance adjustment, we can safely ignore the physical read value provided by the set statistics

horizontally split the table to reduce the table size (sp_spaceuse) 3. upgrade hardware 4. Create an index based on the query conditions, optimize the index, optimize the access mode, and limit the data volume of the result set. Note that the fill factor should be appropriate (preferably the default value 0 ). The index should be as small as possible. Use a colu

some of the cool data query methods provided by LINQ to SQL, we hope these steps can provide a good overview. If you want to learn more LINQ expressions and new language syntaxes supported by C # and VB compilers in vs2008, read the notes I posted earlier: L automatic attributes, object initializer and set Initiator L Extension Method L lamabada expression L

Original: Set STATISTICS io and set STATISTICS time in SQL Server query performance optimizationIn recent times, has been exploring the SQL Server query performance issues, of course, also aimless search for a lot of information, but also from the online great God's articles learned a lot, here, to the great God salute

Label: SQL Server Query optimization method The reasons for the slow query are many, the following are common 1, no index or no index (this is the most common problem of slow query, is the defect of program design)2, I/O throughput is small, forming a bottleneck effect3. No computed column created causes

, the only data we can control is the number of logical reads required to obtain the query results. Therefore, in the query performance adjustment, we can safely ignore the physicalread value provided by the set statistics Io command. (One way to reduce the number of physical reads and speed up the running of SQL Server is to ensure that the physical memory of th

To analyze the performance of a query, you can view {Tagshow (event, '% D6 % B4 % D0 % D0 % BC % C6 % BB % AE ');} "Href =" javascript:; "target =" _ Self ">Execution Plan. Execution Plan description {Tagshow (event, 'SQL ');} "Href =" javascript:; "target =" _ Self ">SQL{Tagshow (event, 'server ');} "Href =" javascript:; "target =" _ Self ">ServerHow the

I. MySql Query Cache 1. Query Cache MySQL Query Cache is used to Cache the SELECT statement we execute and the result set of this statement. The specific technical details of MySql in implementing Query Cache are similar to the typical KV storage, it is to map the SELECT statement and the

Many of my friends may be making mistakes in performance optimization as described below. If you have any need, please refer to the mistakes in SQL Server query performance optimization to get out of the index. Many of my friends may be making mistakes in performance optimization as described below. If you have any need, please refer to the misunderstanding of SQL