如何在SQL Server中获取查询执行计划?

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

预估执行计划

估计的执行计划是由Optimizer在不运行SQL查询的情况下生成的。

为了获得估计的执行计划，您需要在执行查询之前启用SHOWPLAN_ALL设置。

SET SHOWPLAN_ALL ON

现在，当执行以下SQL查询时:

SELECT p.id
FROM post p
WHERE EXISTS (
  SELECT 1
  FROM post_comment pc
  WHERE
    pc.post_id = p.id AND
    pc.review = 'Bingo'
)
ORDER BY p.title
OFFSET 20 ROWS
FETCH NEXT 10 ROWS ONLY

SQL Server将生成以下估计的执行计划:

| NodeId | Parent | LogicalOp            | EstimateRows | EstimateIO  | EstimateCPU | AvgRowSize | TotalSubtreeCost | EstimateExecutions |
|--------|--------|----------------------|--------------|-------------|-------------|------------|------------------|--------------------|
| 1      | 0      | NULL                 | 10           | NULL        | NULL        | NULL       | 0.03374284       | NULL               |
| 2      | 1      | Top                  | 10           | 0           | 3.00E-06    | 15         | 0.03374284       | 1                  |
| 4      | 2      | Distinct Sort        | 30           | 0.01126126  | 0.000504114 | 146        | 0.03373984       | 1                  |
| 5      | 4      | Inner Join           | 46.698       | 0           | 0.00017974  | 146        | 0.02197446       | 1                  |
| 6      | 5      | Clustered Index Scan | 43           | 0.004606482 | 0.0007543   | 31         | 0.005360782      | 1                  |
| 7      | 5      | Clustered Index Seek | 1            | 0.003125    | 0.0001581   | 146        | 0.0161733        | 43                 |

在运行我们想要获得估计执行计划的查询之后，您需要禁用SHOWPLAN_ALL，否则，当前数据库会话将只生成估计的执行计划，而不是执行提供的SQL查询。

SET SHOWPLAN_ALL OFF

SQL Server Management Studio估计计划

在SQL Server Management Studio应用程序中，您可以通过按CTRL+L快捷键轻松获得任何SQL查询的估计执行计划。

实际执行计划

实际的SQL执行计划由Optimizer在运行SQL查询时生成。如果数据库表统计信息是准确的，那么实际计划应该与估计的计划没有太大差异。

要获得SQL Server上的实际执行计划，需要启用STATISTICS IO, TIME, PROFILE设置，如下SQL命令所示:

SET STATISTICS IO, TIME, PROFILE ON

现在，当运行前面的查询时，SQL Server将生成以下执行计划:

| Rows | Executes | NodeId | Parent | LogicalOp            | EstimateRows | EstimateIO  | EstimateCPU | AvgRowSize | TotalSubtreeCost |
|------|----------|--------|--------|----------------------|--------------|-------------|-------------|------------|------------------|
| 10   | 1        | 1      | 0      | NULL                 | 10           | NULL        | NULL        | NULL       | 0.03338978       |
| 10   | 1        | 2      | 1      | Top                  | 1.00E+01     | 0           | 3.00E-06    | 15         | 0.03338978       |
| 30   | 1        | 4      | 2      | Distinct Sort        | 30           | 0.01126126  | 0.000478783 | 146        | 0.03338679       |
| 41   | 1        | 5      | 4      | Inner Join           | 44.362       | 0           | 0.00017138  | 146        | 0.02164674       |
| 41   | 1        | 6      | 5      | Clustered Index Scan | 41           | 0.004606482 | 0.0007521   | 31         | 0.005358581      |
| 41   | 41       | 7      | 5      | Clustered Index Seek | 1            | 0.003125    | 0.0001581   | 146        | 0.0158571        |
 
SQL Server parse and compile time:
   CPU time = 8 ms, elapsed time = 8 ms.
 
(10 row(s) affected)
Table 'Worktable'. Scan count 0, logical reads 0, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
Table 'post'. Scan count 0, logical reads 116, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
Table 'post_comment'. Scan count 1, logical reads 5, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
 
(6 row(s) affected)
 
SQL Server Execution Times:
   CPU time = 0 ms,  elapsed time = 1 ms.

运行查询后，我们感兴趣的是获得实际的执行计划，你需要禁用STATISTICS IO, TIME, PROFILE ON设置，如下所示:

SET STATISTICS IO, TIME, PROFILE OFF

SQL Server Management Studio实际计划

在SQL Server Management Studio应用程序中，您可以通过按CTRL+M快捷键轻松获得任何SQL查询的估计执行计划。

2019-09-23 19:28:18

其他回答

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。

2021-03-30 14:25:57

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

2018-05-25 15:26:03

假设您正在使用Microsoft SQL Server Management Studio

对于估计的查询计划，可以按Ctrl + L或以下按钮。

对于“实际查询计划”，可以按“Ctrl +” M或以下按钮，然后执行查询。

对于实时查询计划，(仅在SSMS 2016中)在执行查询之前使用以下按钮。

2016-09-09 19:25:22

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。

2015-11-11 19:06:33