我有很多查询，我想用 sql server management studio 上的 Include Actual Execution Plan 功能测试每个查询
但是，对于 1m + 查询，我无法手动执行此操作
所以我想知道我是否可以使用包含实际执行计划功能以编程方式（来自 c#）执行它们，并查看 SQL 服务器是否建议任何索引
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首先，在我介绍如何在代码中获取实际执行计划并找到报告需要索引的计划之前，我建议您使用Database Engine Tuning Adviser (DTA)，您可以向它提供所有查询，它将处理它们，告诉您可能的索引、统计信息和许多其他有助于规划查询的内容。
比给它一个 1m+ 查询列表更好的是，您可以从服务器获取正在运行的实际查询的跟踪，它将专注于占用最多时间的查询。
要回答您的原始问题，您需要SET STATISTICS XML ON在连接开始时添加，这将为您提供您显示的 GUI 所基于的 XML 数据。（有关获取计划的更多信息，请参见此处）。一旦你这样做了，你的查询将返回一个额外的结果集，其中包含第一列第一行中计划的 xml。
这是一个快速而肮脏的功能。
private static string GetXmlPlanForQuery(string queryText)
{
string result = null;
using (var connection = new SqlConnection(connectionString))
using (var command = new SqlCommand())
{
connection.Open();
command.Connection = connection;
//Enable the statistics.
command.CommandText = "SET STATISTICS XML ON";
command.ExecuteNonQuery();
//Run through the query, keeping the first row first column of the last result set.
command.CommandText = queryText;
using (var reader = command.ExecuteReader())
{
object lastValue = null;
do
{
if (reader.Read())
{
lastValue = reader.GetValue(0);
}
} while (reader.NextResult());
if (lastValue != null)
{
result = lastValue as string;
}
}
}
return result;
}
这是它为select TOTAL_SALES from clients where ACTIVE = 0;我在本地数据库之一上运行的查询返回的 XML。
<?xml version="1.0"?>
<ShowPlanXML xmlns="http://schemas.microsoft.com/sqlserver/2004/07/showplan" Version="1.2" Build="11.0.5058.0">
<BatchSequence>
<Batch>
<Statements>
<StmtSimple StatementText="SELECT [TOTAL_SALES] FROM [clients] WHERE [ACTIVE]=@1" StatementId="1" StatementCompId="1" StatementType="SELECT" RetrievedFromCache="false" StatementSubTreeCost="0.0767454" StatementEstRows="315" StatementOptmLevel="FULL" QueryHash="0x708AE72DD31A316" QueryPlanHash="0x214EA79FF76E6771" StatementOptmEarlyAbortReason="GoodEnoughPlanFound">
<StatementSetOptions QUOTED_IDENTIFIER="true" ARITHABORT="false" CONCAT_NULL_YIELDS_NULL="true" ANSI_NULLS="true" ANSI_PADDING="true" ANSI_WARNINGS="true" NUMERIC_ROUNDABORT="false"/>
<QueryPlan DegreeOfParallelism="1" CachedPlanSize="16" CompileTime="1" CompileCPU="1" CompileMemory="192">
<MissingIndexes>
<MissingIndexGroup Impact="94.0522">
<MissingIndex Database="[exampleDb]" Schema="[dbo]" Table="[CLIENTS]">
<ColumnGroup Usage="EQUALITY">
<Column Name="[ACTIVE]" ColumnId="15"/>
</ColumnGroup>
<ColumnGroup Usage="INCLUDE">
<Column Name="[TOTAL_SALES]" ColumnId="18"/>
</ColumnGroup>
</MissingIndex>
</MissingIndexGroup>
</MissingIndexes>
<MemoryGrantInfo SerialRequiredMemory="0" SerialDesiredMemory="0"/>
<OptimizerHardwareDependentProperties EstimatedAvailableMemoryGrant="830838" EstimatedPagesCached="207709" EstimatedAvailableDegreeOfParallelism="2"/>
<RelOp NodeId="0" PhysicalOp="Clustered Index Scan" LogicalOp="Clustered Index Scan" EstimateRows="315" EstimateIO="0.0749769" EstimateCPU="0.0017685" AvgRowSize="16" EstimatedTotalSubtreeCost="0.0767454" TableCardinality="1465" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row">
<OutputList>
<ColumnReference Database="[exampleDb]" Schema="[dbo]" Table="[CLIENTS]" Column="TOTAL_SALES"/>
</OutputList>
<RunTimeInformation>
<RunTimeCountersPerThread Thread="0" ActualRows="315" ActualEndOfScans="1" ActualExecutions="1"/>
</RunTimeInformation>
<IndexScan Ordered="0" ForcedIndex="0" ForceScan="0" NoExpandHint="0">
<DefinedValues>
<DefinedValue>
<ColumnReference Database="[exampleDb]" Schema="[dbo]" Table="[CLIENTS]" Column="TOTAL_SALES"/>
</DefinedValue>
</DefinedValues>
<Object Database="[exampleDb]" Schema="[dbo]" Table="[CLIENTS]" Index="[imp_clpk_CLIENTS]" IndexKind="Clustered"/>
<Predicate>
<ScalarOperator ScalarString="[exampleDb].[dbo].[CLIENTS].[ACTIVE]=(0)">
<Compare CompareOp="EQ">
<ScalarOperator>
<Identifier>
<ColumnReference Database="[exampleDb]" Schema="[dbo]" Table="[CLIENTS]" Column="ACTIVE"/>
</Identifier>
</ScalarOperator>
<ScalarOperator>
<Const ConstValue="(0)"/>
</ScalarOperator>
</Compare>
</ScalarOperator>
</Predicate>
</IndexScan>
</RelOp>
<ParameterList>
<ColumnReference Column="@1" ParameterCompiledValue="(0)" ParameterRuntimeValue="(0)"/>
</ParameterList>
</QueryPlan>
</StmtSimple>
</Statements>
</Batch>
</BatchSequence>
</ShowPlanXML>
现在，因为微软非常好，如果你导航到 XML 中列出的命名空间，你实际上可以得到一份.xsd格式的副本。然后，您可以从开发人员的命令提示符处执行操作xsd showplanxml.xsd /classes，它会为您提供一个showplanxml.cs可以与XmlSerializer.
这是一个小示例程序，它在缺少的索引上执行调试器中断。
static void Main(string[] args)
{
string result = GetXmlPlanForQuery("select TOTAL_SALES from clients where ACTIVE = 0;");
XmlSerializer ser = new XmlSerializer(typeof(ShowPlanXML));
var plan = (ShowPlanXML)ser.Deserialize(new StringReader(result));
var missingIndexes =
plan.BatchSequence.SelectMany(x => x)
.SelectMany(x => x.Items)
.OfType<StmtSimpleType>()
.Select(x => x.QueryPlan)
.Where(x => x.MissingIndexes != null && x.MissingIndexes.Any());
foreach (var queryPlan in missingIndexes)
{
//This will hit for each statement in the query that was missing a index, check queryPlan.MissingIndexes to see the indexes that are missing.
Debugger.Break();
}
Console.WriteLine("Done");
Console.ReadLine();
}
我使用 XmlSerializer 并将其反序列化为一个类，但您可以轻松地将其加载到 XDocument 中，然后使用XPath查找所有名为MissingIndex.
于 2014-09-16T23:52:15.757 回答