在Microsoft SQL Server如何获得查询/存储过程的查询执行计划?


当前回答

从SQL Server 2016+开始,引入了查询存储功能来监控性能。它提供了对查询计划选择和性能的洞察。 它并不是跟踪或扩展事件的完全替代,但随着它从一个版本到另一个版本的发展,我们可能会在SQL Server的未来版本中得到一个功能齐全的查询存储。 查询存储的主要流程

SQL Server existing components interact with query store by utilising Query Store Manager. Query Store Manager determines which Store should be used and then passes execution to that store (Plan or Runtime Stats or Query Wait Stats) Plan Store - Persisting the execution plan information Runtime Stats Store - Persisting the execution statistics information Query Wait Stats Store - Persisting wait statistics information. Plan, Runtime Stats and Wait store uses Query Store as an extension to SQL Server.

Enabling the Query Store: Query Store works at the database level on the server. Query Store is not active for new databases by default. You cannot enable the query store for the master or tempdb database. Available DMV sys.database_query_store_options (Transact-SQL) Collect Information in the Query Store: We collect all the available information from the three stores using Query Store DMV (Data Management Views). Query Plan Store: Persisting the execution plan information and it is accountable for capturing all information that is related to query compilation. sys.query_store_query (Transact-SQL) sys.query_store_plan (Transact-SQL) sys.query_store_query_text (Transact-SQL) Runtime Stats Store: Persisting the execution statistics information and it is probably the most frequently updated store. These statistics represent query execution data. sys.query_store_runtime_stats (Transact-SQL) Query Wait Stats Store: Persisting and capturing wait statistics information. sys.query_store_wait_stats (Transact-SQL)

注意:查询等待统计数据存储仅在SQL Server 2017+中可用

其他回答

查询计划可以通过query_post_execution_showplan事件从扩展事件会话中获得。下面是一个XEvent会话示例:

/*
    Generated via "Query Detail Tracking" template.
*/
CREATE EVENT SESSION [GetExecutionPlan] ON SERVER 
ADD EVENT sqlserver.query_post_execution_showplan(
    ACTION(package0.event_sequence,sqlserver.plan_handle,sqlserver.query_hash,sqlserver.query_plan_hash,sqlserver.session_id,sqlserver.sql_text,sqlserver.tsql_frame,sqlserver.tsql_stack)),

/* Remove any of the following events (or include additional events) as desired. */
ADD EVENT sqlserver.error_reported(
    ACTION(package0.event_sequence,sqlserver.client_app_name,sqlserver.database_id,sqlserver.plan_handle,sqlserver.query_hash,sqlserver.query_plan_hash,sqlserver.session_id,sqlserver.sql_text,sqlserver.tsql_frame,sqlserver.tsql_stack)
    WHERE ([package0].[greater_than_uint64]([sqlserver].[database_id],(4)) AND [package0].[equal_boolean]([sqlserver].[is_system],(0)))),
ADD EVENT sqlserver.module_end(SET collect_statement=(1)
    ACTION(package0.event_sequence,sqlserver.client_app_name,sqlserver.database_id,sqlserver.plan_handle,sqlserver.query_hash,sqlserver.query_plan_hash,sqlserver.session_id,sqlserver.sql_text,sqlserver.tsql_frame,sqlserver.tsql_stack)
    WHERE ([package0].[greater_than_uint64]([sqlserver].[database_id],(4)) AND [package0].[equal_boolean]([sqlserver].[is_system],(0)))),
ADD EVENT sqlserver.rpc_completed(
    ACTION(package0.event_sequence,sqlserver.client_app_name,sqlserver.database_id,sqlserver.plan_handle,sqlserver.query_hash,sqlserver.query_plan_hash,sqlserver.session_id,sqlserver.sql_text,sqlserver.tsql_frame,sqlserver.tsql_stack)
    WHERE ([package0].[greater_than_uint64]([sqlserver].[database_id],(4)) AND [package0].[equal_boolean]([sqlserver].[is_system],(0)))),
ADD EVENT sqlserver.sp_statement_completed(SET collect_object_name=(1)
    ACTION(package0.event_sequence,sqlserver.client_app_name,sqlserver.database_id,sqlserver.plan_handle,sqlserver.query_hash,sqlserver.query_plan_hash,sqlserver.session_id,sqlserver.sql_text,sqlserver.tsql_frame,sqlserver.tsql_stack)
    WHERE ([package0].[greater_than_uint64]([sqlserver].[database_id],(4)) AND [package0].[equal_boolean]([sqlserver].[is_system],(0)))),
ADD EVENT sqlserver.sql_batch_completed(
    ACTION(package0.event_sequence,sqlserver.client_app_name,sqlserver.database_id,sqlserver.plan_handle,sqlserver.query_hash,sqlserver.query_plan_hash,sqlserver.session_id,sqlserver.sql_text,sqlserver.tsql_frame,sqlserver.tsql_stack)
    WHERE ([package0].[greater_than_uint64]([sqlserver].[database_id],(4)) AND [package0].[equal_boolean]([sqlserver].[is_system],(0)))),
ADD EVENT sqlserver.sql_statement_completed(
    ACTION(package0.event_sequence,sqlserver.client_app_name,sqlserver.database_id,sqlserver.plan_handle,sqlserver.query_hash,sqlserver.query_plan_hash,sqlserver.session_id,sqlserver.sql_text,sqlserver.tsql_frame,sqlserver.tsql_stack)
    WHERE ([package0].[greater_than_uint64]([sqlserver].[database_id],(4)) AND [package0].[equal_boolean]([sqlserver].[is_system],(0)))) 
ADD TARGET package0.ring_buffer
WITH (MAX_MEMORY=4096 KB,EVENT_RETENTION_MODE=ALLOW_SINGLE_EVENT_LOSS,MAX_DISPATCH_LATENCY=30 SECONDS,MAX_EVENT_SIZE=0 KB,MEMORY_PARTITION_MODE=NONE,TRACK_CAUSALITY=ON,STARTUP_STATE=OFF)
GO

创建会话后,(在SSMS中)转到对象资源管理器并深入到管理|扩展事件|会话。右键单击“GetExecutionPlan”会话并启动它。再次右键选择“观看实时数据”。

接下来,打开一个新的查询窗口并运行一个或多个查询。以下是AdventureWorks的一个例子:

USE AdventureWorks;
GO

SELECT p.Name AS ProductName, 
    NonDiscountSales = (OrderQty * UnitPrice),
    Discounts = ((OrderQty * UnitPrice) * UnitPriceDiscount)
FROM Production.Product AS p 
INNER JOIN Sales.SalesOrderDetail AS sod
    ON p.ProductID = sod.ProductID 
ORDER BY ProductName DESC;
GO

过一会儿,您应该在“GetExecutionPlan: Live Data”选项卡中看到一些结果。单击网格中的query_post_execution_showplan事件之一,然后单击网格下面的“Query Plan”选项卡。它应该看起来像这样:

编辑:XEvent代码和屏幕截图是从SQL/SSMS 2012 w/ SP2生成的。如果您使用的是SQL 2008/R2,则可以调整脚本以使其运行。但那个版本没有GUI,所以你需要提取showplan XML,保存为*。并在SSMS中打开。这是麻烦的。XEvents在SQL 2005或更早的版本中并不存在。所以,如果你没有使用SQL 2012或更高版本,我强烈建议你使用这里发布的其他答案之一。

除了前面所说的,还有一件重要的事情需要知道。

Query plans are often too complex to be represented by the built-in XML column type which has a limitation of 127 levels of nested elements. That is one of the reasons why sys.dm_exec_query_plan may return NULL or even throw an error in earlier MS SQL versions, so generally it's safer to use sys.dm_exec_text_query_plan instead. The latter also has a useful bonus feature of selecting a plan for a particular statement rather than the whole batch. Here's how you use it to view plans for currently running statements:

SELECT p.query_plan
FROM sys.dm_exec_requests AS r
OUTER APPLY sys.dm_exec_text_query_plan(
                r.plan_handle,
                r.statement_start_offset,
                r.statement_end_offset) AS p

然而,与XML列相比,结果表中的文本列不是很方便。为了能够单击要在单独的选项卡中作为图表打开的结果,而不必将其内容保存到文件中,您可以使用一个小技巧(记住您不能只使用CAST(…AS XML)),尽管这将只适用于单行:

SELECT Tag = 1, Parent = NULL, [ShowPlanXML!1!!XMLTEXT] = query_plan
FROM sys.dm_exec_text_query_plan(
                -- set these variables or copy values
                -- from the results of the above query
                @plan_handle,
                @statement_start_offset,
                @statement_end_offset)
FOR XML EXPLICIT

您也可以通过powershell使用SET STATISTICS XML ON来获得实际的计划。我写它是为了将多语句计划合并为一个计划;

    ########## BEGIN : SCRIPT VARIABLES #####################
    [string]$server = '.\MySQLServer'
    [string]$database = 'MyDatabase'
    [string]$sqlCommand = 'EXEC sp_ExampleSproc'
    [string]$XMLOutputFileName = 'sp_ExampleSproc'
    [string]$XMLOutputPath = 'C:\SQLDumps\ActualPlans\'
    ########## END   : SCRIPT VARIABLES #####################

    #Set up connection
    $connectionString = "Persist Security Info=False;Integrated Security=true;Connection Timeout=0;Initial Catalog=$database;Server=$server"
    $connection = new-object system.data.SqlClient.SQLConnection($connectionString)

    #Set up commands
    $command = new-object system.data.sqlclient.sqlcommand($sqlCommand,$connection)
    $command.CommandTimeout = 0
    $commandXMLActPlanOn = new-object system.data.sqlclient.sqlcommand("SET STATISTICS XML ON",$connection)
    $commandXMLActPlanOff = new-object system.data.sqlclient.sqlcommand("SET STATISTICS XML OFF",$connection)

    $connection.Open()

    #Enable session XML plan
    $result = $commandXMLActPlanOn.ExecuteNonQuery()

    #Execute SP and return resultsets into a dataset
    $adapter = New-Object System.Data.sqlclient.sqlDataAdapter $command
    $dataset = New-Object System.Data.DataSet
    $adapter.Fill($dataSet) | Out-Null

    #Set up output file name and path
    [string]$fileNameDateStamp = get-date -f yyyyMMdd_HHmmss
    [string]$XMLOutputFilePath = "$XMLOutputPath$XMLOutputFileName`_$fileNameDateStamp.sqlplan"

    #Pull XML plans out of dataset and merge into one multi-statement plan
    [int]$cntr = 1
    ForEach($table in $dataset.Tables)
    {
            if($table.Columns[0].ColumnName -eq "Microsoft SQL Server 2005 XML Showplan")
            {

                [string]$fullXMLPlan = $Table.rows[0]."Microsoft SQL Server 2005 XML Showplan"

                if($cntr -eq 1)
                    {

                    [regex]$rx = "\<ShowPlanXML xmlns\=.{1,}\<Statements\>"
                    [string]$startXMLPlan = $rx.Match($fullXMLPlan).Value
                    [regex]$rx = "\<\/Statements\>.{1,}\<\/ShowPlanXML\>"
                    [string]$endXMLPlan = $rx.Match($fullXMLPlan).Value

                    $startXMLPlan | out-file -Append -FilePath $XMLOutputFilePath

                    }

                [regex]$rx = "\<StmtSimple.{1,}\<\/StmtSimple\>"
                [string]$bodyXMLPlan = $rx.Match($fullXMLPlan).Value

                $bodyXMLPlan | out-file -Append -FilePath $XMLOutputFilePath

                $cntr += 1
            } 
    }

    $endXMLPlan | out-file -Append -FilePath $XMLOutputFilePath

    #Disable session XML plan
    $result = $commandXMLActPlanOff.ExecuteNonQuery()

    $connection.Close()

在SQL Server Management Studio:

“Ctrl + M”将生成实际执行计划

“Ctrl + L”将生成估计执行计划

“Shift + Alt + S”为客户端统计

“Ctrl + Alt + P”用于SQL Server Profiler中的跟踪查询。

与SQL Server Management Studio(已经解释过了)一样,Datagrip也可以在这里解释。

右键单击SQL语句,并选择Explain plan。 在Output窗格中,单击Plan。 默认情况下,您将看到查询的树表示形式。去看 查询计划时,单击“显示可视化”图标,或按 Ctrl + Shift + Alt + U