Oracle中，将char或varchar数据类型转换为date数据类型的函数是？（） A: date B: to_date C: todate D: ctodate

Oracle中，下面什么函数将char或varchar数据类型转换为date数据类型？（） A: date B: to_date C: ctodate D: todate

长篇阅读Passage1 TheTouch-ScreenGeneration A)Onachillydaylastspring,afewdozendevelopersofchildren’sapps(应用程序)forphonesandtablets(平板电脑)gatheredatanoldbeachresortinMonterey,California,toshowofftheirgames.ThegatheringwasorganizedbyWarrenBuckleitner,alongtimereviewerofinteractivechildren’smedia.Buckleitnerspentthebreakstestingwhetherhisownremote-controlhelicoptercouldreachthehall’ssecondstory,whilevariouschildrenwhohadcomewiththeirparentslookedupinawe(敬畏)anddelight.Butmostlytheylookeddown,attheiPadsandothertabletsdisplayedaroundthehalllikesomanyopenboxesofcandy.Iwalkedaroundandtalkedwithdevelopers,andseveralquotedafamoussayingofMariaMontessori’s,“Thehandsaretheinstrumentsofman’sintelligence.” B)What,really,wouldMariaMontessorihavemadeofthisscene?The30orsochildrenherewerenotdownattheshorepoking(戳)theirfingersinthesandorrunningthemalongmossystonesorpickingseashells.Insteadtheywereallinside,aloneoringroupsoftwoorthree,theirfacesafewinchesfromascreen,theirhandsdoingthingsMontessorisurelydidnotimagine. C)In2011,theAmericanAcademyofPediatricsupdateditspolicyonveryyoungchildrenandmedia.In1999,thegrouphaddiscouragedtelevisionviewingforchildrenyoungerthan2,citingresearchonbraindevelopmentthatshowedthisagegroup’scriticalneedfor“directinteractionswithparentsandothersignificantcaregivers.”Theupdatedreportbeganbyacknowledgingthatthingshadchangedsignificantlysincethen.In2006,90%ofparentssaidthattheirchildrenyoungerthan2consumedsomeformofelectronicmedia.Nevertheless,thegrouptooklargelythesameapproachitdidin1999,uniformlydiscouragingpassivemediause,onanytypeofscreen,forthesekids.(Forolderchildren,theacademynoted,“high-qualityprograms”couldhave“educationalbenefits.”)The2011reportmentioned“smartcellphone”and“newscreen”technologies,butdidnotaddressinteractiveapps.Nordiditbringupthepossibilitythathaslikelyoccurredtothose90%ofAmericanparentsthatsomegoodmightcomefromthoselittleswiping(在电子产品上刷)fingers. D)Ihadcometothedevelopers’conferencepartlybecauseIhopedthatthisparticularsetofparents,enthusiasticastheywereaboutinteractivemedia,mighthelpmeoutofthisproblem,thattheymightoffersomeguidingprincipleforAmericanparentswhoareclearlynevergoingtomeettheacademy’sideals,andatsomeleveldonotwantto.Perhapsthisgroupwouldbeabletoexpressclearlysomebenefitsofthenewtechnologythatthemorecautiousdoctorsweren’treadytoaddress. E)IfellintoconversationwithawomanwhohadhelpeddevelopMontessoriLetterSounds,anappthatteachespreschoolerstheMontessorimethodsofspelling.ShewasaformerMontessoriteacherandamotheroffour.Imyselfhavethreechildrenwhoareallfansofthetouchscreen.Whatgamesdidherkidsliketoplay,Iasked,hopingforsuggestionsIcouldtakehome. “Theydon’tplayallthatmuch.” Really?Whynot? “BecauseIdon’tallowit.Wehavearuleofnoscreentimeduringtheweek,unlessit’sclearlyeducational.” Noscreentime?Noneatall?Thatseemsattheouteredgeofrestrictive,evenbythestandardsofovercontrollingparents. “Ontheweekends,theycanplay.Igivethemalimitofhalfanhourandthenstop.Enough.” F)HeranswersosurprisedmethatIdecidedtoasksomeoftheotherdeveloperswhowerealsoparentswhattheirdomesticgroundrulesforscreentimewere.Onesaidonlyonairplanesandlongcarrides.AnothersaidWednesdaysandweekends,forhalfanhour.Themostpermissivesaidhalfanhouraday,whichwasaboutmyruleathome.AtonepointIsatwithoneofthebiggestdevelopersofe-bookappsforkids,andhisfamily.Thesmallkidwasstartingtofussinherhighchair,sothemomstuckaniPadinfrontofherandplayedashortmoviesoeveryoneelsecouldenjoytheirlunch.Whenshesawmewatching,shegavemetheuniversaltenselookofmotherswhofeeltheyarebeingjudged.“Athome,”sheassuredme,“IonlyletherwatchmoviesinSpanish.” G)Bytheirreactions,theseparentsmademeunderstandtheproblemofourage:astechnologybecomesalmosteverywhereinourlives,Americanparentsarebecomingmore,notless,distrustfulofwhatitmightbedoingtotheirchildren.Technologicalabilityhasnot,forparents,translatedintocomfortandease.Ontheonehand,parentswanttheirchildrentoswimexpertlyinthedigitalstreamthattheywillhavetonavigate(航行)alltheirlives;ontheotherhand,theyfearthattoomuchdigitalmedia,tooearly,willsinkthem.Parentsenduptreatingtabletsasprecisionsurgical(外科的)instruments,devicesthatmightperformmiraclesfortheirchild’sIQandhelphimwinsomegreatroboticscompetition—butonlyiftheyareusedjustso.Otherwise,theirchildcouldenduponeofthosesad,palecreatureswhocan’tmakeeyecontactandhasagirlfriendwholivesonlyinthevirtualworld. H)NormanRockwell,a20th-centuryartist,neverpaintedBoySwipingFingeronScreen,andourownvisionofaperfectchildhoodhasneverbeenadjustedtoaccommodatethatnow-commonscene.Addtothatourmodernfearthateveryparentingdecisionmayhavelastingconsequences—thateveryminuteofenrichmentlostormindlessentertainmentindulged(放纵的)willadduptosomepermanenthandicap(障碍)inthefuture—andyouhavedeepguiltandconfusion.Todate,nobodyofresearchhasprovedthattheiPadwillmakeyourpreschoolersmarterorteachhertospeakChinese,oralternativelythatitwillrusthernervoussystem—thedevicehasbeenoutforonlythreeyears,notmuchmorethanthetimeittakessomeacademicstofindfundingandgatherresearchsubjects.Sowhatisaparenttodo? 1.Theauthorattendedtheconference,hopingtofindsomeguidingprinciplesforparentingintheelectronicage. 2.Americanparentsarebecomingmoredoubtfulaboutthebenefitstechnologyissaidtobringtotheirchildren. 3.Someexpertsbelievethathumanintelligencedevelopsbytheuseofhands. 4.TheauthorfoundaformerMontessoriteacherexercisingstrictcontroloverherkids’screentime. 5.Researchshowsinteractionwithpeopleiskeytobabies’braindevelopment. 6.SofartherehasbeennoscientificproofoftheeducationalbenefitsofiPads. 7.Americanparentsworrythatoveruseoftabletswillcreateproblemswiththeirkids’interpersonalrelationships. 8.Theauthorexpecteddevelopersofchildren’sappstospecifythebenefitsofthenewtechnology. 9.ThekidsatthegatheringweremorefascinatedbytheiPadsthanbythehelicopter. 10.Theauthorpermitsherchildrentousethescreenforatmosthalfanhouraday. 四级长篇阅读-四周的练习-第15周.docx/js/editor20150812/dialogs/attachment_new/fileTypeImages/icon_doc.gif