sql,server,如何查看执行计划

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1、为了适应公司新战略的发展，保障停车场安保新项目的正常、顺利开展，特制定安保从业人员的业务技能及个人素质的培训计划sql,server,如何查看执行计划　　看懂执行计划　　例子1　　以AdventureWorks的DatabaseLog查询为例：　　SELECT*FROM[AdventureWorksXXR2].[dbo].[DatabaseLog]　　?Cachedplansize–howmuchmemorytheplangeneratedbythisquerywilltakeupinstoredprocedurecache.Thisisausefulnumberwheninves

2、tigatingcacheperformanceissuesbecauseyou'llbeabletoseewhichplansaretakingupmorememory.　　?EstimatedOperatorCost–we'vealreadyseenthisasthepercentagecostinFigure1.　　?EstimatedSubtreeCost–tellsustheaccumulatedoptimizercostassignedtothisstepandallprevioussteps,butremembertoreadfromrighttoleft.Thisn

3、umberismeaninglessintherealworld,butisamathematicalevaluationusedbythequeryoptimizertodeterminethecostoftheoperatorinquestion;itrepresentstheamountoftimethattheoptimizerthinksthisoperatorwilltake.　　?目的-通过该培训员工可对保安行业有初步了解，并感受到安保行业的发展的巨大潜力，可提升其的专业水平，并确保其在这个行业的安全感。为了适应公司新战略的发展，保障停车场安保新项目的正常、顺利开展，

4、特制定安保从业人员的业务技能及个人素质的培训计划　　Estimatednumberofrows　　–calculatedbasedonthestatisticsavailabletotheoptimizerforthetableorindexinquestion.　　Thelogicaloperatorsaretheresultsoftheoptimizer'scalculationsforwhatshouldhappenwhenthequeryexecutes.Thephysicaloperatorsrepresentwhatactuallyoccurred.Thelogical

5、andphysicaloperatorsareusuallythesame,butnotalways　　TheSubtreeissimplythesectionoftheexecutiontreethatwehavelookedatsofar,workingrighttoleftagain,andtoptobottom.Allestimationsarebasedonthestatisticsavailableonthecolumnsandindexesinanytable.　　TheI/OCostandCPUcostarenotactualoperators,butrathert

6、hecostnumbersassignedbytheQueryOptimizerduringitscalculations.Thesenumbersareusefulwhendetermining目的-通过该培训员工可对保安行业有初步了解，并感受到安保行业的发展的巨大潜力，可提升其的专业水平，并确保其在这个行业的安全感。为了适应公司新战略的发展，保障停车场安保新项目的正常、顺利开展，特制定安保从业人员的业务技能及个人素质的培训计划　　whethermostofthecostisI/O-based(asinthiscase),orifwe'reputtingaloadontheCPU

7、.Abiggernumbermeansmoreprocessinginthisarea.　　You'llnotethat,inthiscase,theoperatorcostandthesubtreecostarethesame,sincethetablescanistheonlyoperator.Formorecomplextrees,withmoreoperators,you'llseethatthecostaccumulatesastheindividualco