sql,server,如何查看執(zhí)行計(jì)劃

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1、為了適應(yīng)公司新戰(zhàn)略的發(fā)展，保障停車(chē)場(chǎng)安保新項(xiàng)目的正常、順利開(kāi)展，特制定安保從業(yè)人員的業(yè)務(wù)技能及個(gè)人素質(zhì)的培訓(xùn)計(jì)劃sql,server,如何查看執(zhí)行計(jì)劃　　看懂執(zhí)行計(jì)劃　　例子1　　以AdventureWorks的DatabaseLog查詢(xún)?yōu)槔骸　ELECT*FROM[AdventureWorksXXR2].[dbo].[DatabaseLog]　　?Cachedplansize–howmuchmemorytheplangeneratedbythisquerywilltakeupinstoredprocedurecache.Thisisausefulnumberwheninves

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

3、umberismeaninglessintherealworld,butisamathematicalevaluationusedbythequeryoptimizertodeterminethecostoftheoperatorinquestion;itrepresentstheamountoftimethattheoptimizerthinksthisoperatorwilltake.　　?目的-通過(guò)該培訓(xùn)員工可對(duì)保安行業(yè)有初步了解，并感受到安保行業(yè)的發(fā)展的巨大潛力，可提升其的專(zhuān)業(yè)水平，并確保其在這個(gè)行業(yè)的安全感。為了適應(yīng)公司新戰(zhàn)略的發(fā)展，保障停車(chē)場(chǎng)安保新項(xiàng)目的正常、順利開(kāi)展，

4、特制定安保從業(yè)人員的業(yè)務(wù)技能及個(gè)人素質(zhì)的培訓(xùn)計(jì)劃　　Estimatednumberofrows　　–calculatedbasedonthestatisticsavailabletotheoptimizerforthetableorindexinquestion.　　Thelogicaloperatorsaretheresultsoftheoptimizer'scalculationsforwhatshouldhappenwhenthequeryexecutes.Thephysicaloperatorsrepresentwhatactuallyoccurred.Thelogical

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

6、hecostnumbersassignedbytheQueryOptimizerduringitscalculations.Thesenumbersareusefulwhendetermining目的-通過(guò)該培訓(xùn)員工可對(duì)保安行業(yè)有初步了解，并感受到安保行業(yè)的發(fā)展的巨大潛力，可提升其的專(zhuān)業(yè)水平，并確保其在這個(gè)行業(yè)的安全感。為了適應(yīng)公司新戰(zhàn)略的發(fā)展，保障停車(chē)場(chǎng)安保新項(xiàng)目的正常、順利開(kāi)展，特制定安保從業(yè)人員的業(yè)務(wù)技能及個(gè)人素質(zhì)的培訓(xùn)計(jì)劃　　whethermostofthecostisI/O-based(asinthiscase),orifwe'reputtingaloadontheCPU

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