Video: Dab tsi yog qhov sib txawv ntawm cov ntaub ntawv thib ob thiab thawj zaug?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Cov ntaub ntawv thib ob yog cov uas twb muaj lawm cov ntaub ntawv , sau los ntawm cov koom haum soj ntsuam thiab cov koom haum ua ntej. Cov ntaub ntawv tseem ceeb yog lub sijhawm tiag tiag cov ntaub ntawv hos cov ntaub ntawv thib ob yog ib qho uas cuam tshuam rau yav dhau los. Cov ntaub ntawv tseem ceeb Cov ntaub ntawv sau muaj xws li kev tshawb fawb, kev soj ntsuam, kev sim, daim ntawv nug, kev xam phaj tus kheej, thiab lwm yam.
Kuj paub, qhov twg yog cov ntaub ntawv thawj lossis cov ntaub ntawv thib ob zoo dua?
Cov ntaub ntawv tseem ceeb muaj nyob rau hauv daim ntawv nyoos whereas cov ntaub ntawv thib ob yog lub refined daim ntawv ntawm thawj cov ntaub ntawv . Nws kuj tuaj yeem hais tau tias cov ntaub ntawv thib ob tau txais thaum txoj kev txheeb cais raug siv rau thawj cov ntaub ntawv . Cov ntaub ntawv sau los ntawm thawj qhov chaw yog ntau txhim khu kev qha thiab raug raws li piv rau cov theem nrab qhov chaw.
Tsis tas li ntawd, qhov txawv ntawm cov ntaub ntawv tseem ceeb thiab theem nrab yog dab tsi? Thawj yog cov ntaub ntawv uas koj sau. Secondary yog cov ntaub ntawv uas twb tau sau tseg lawm, thiab muaj feem cuam tshuam rau koj qhov kev tshawb fawb.
Qhov twg yog qhov zoo dua los siv cov ntaub ntawv thib ob lossis cov ntaub ntawv tseem ceeb?
Cov ntaub ntawv tseem ceeb yog txhim khu kev qha tshaj cov ntaub ntawv thib ob . Nws yog vim thawj cov ntaub ntawv yog sau los ntawm kev ua thawj tshawb fawb thiab tsis dhau theem nrab qhov chaw uas tej zaum yuav raug rau qee qhov yuam kev lossis tsis sib xws thiab tej zaum yuav muaj cov ntaub ntawv tsis tu ncua. Cov ntaub ntawv thib ob tsawg dua ntseeg tau tshaj thawj cov ntaub ntawv.
Dab tsi yog hom ntawm cov ntaub ntawv tseem ceeb?
Muaj ntau hom ntaub ntawv tseem ceeb thiab lawv siv raws li hom kev kawm. Qee qhov kev siv tseem ceeb tshaj plaws ntawm thawj sau cov ntaub ntawv suav nrog kev soj ntsuam , kev xam phaj, nqe lus nug thiab kev sim.
Pom zoo:
Dab tsi yog qhov txawv ntawm XML cov ntaub ntawv thiab cov ntaub ntawv sib txheeb?
Qhov sib txawv loj ntawm XML cov ntaub ntawv thiab cov ntaub ntawv sib txheeb Ib daim ntawv XML muaj cov ntaub ntawv hais txog kev sib raug zoo ntawm cov ntaub ntawv rau ib leeg nyob rau hauv daim ntawv ntawm hierarchy. Nrog rau tus qauv kev sib raug zoo, tib hom kev sib raug zoo uas tuaj yeem txhais tau yog cov lus niam txiv thiab cov rooj sib raug zoo
Dab tsi yog qhov sib txawv ntawm pab pawg cov ntaub ntawv thiab cov ntaub ntawv tsis yog pawg?
Ob leeg yog cov ntaub ntawv muaj txiaj ntsig ntawm cov ntaub ntawv tab sis qhov sib txawv ntawm lawv yog cov ntaub ntawv tsis muaj ntaub ntawv yog rawdata. Qhov no txhais tau hais tias nws nyuam qhuav tau sau tab sis tsis txheeb rau hauv ib pawg lossis cov chav kawm. Ntawm qhov tod tes, groupeddata yog cov ntaub ntawv uas tau teeb tsa ua pawg los ntawm cov ntaub ntawv nyoos
Dab tsi yog qhov sib txawv ntawm cov ntaub ntawv sib sau ua ke thiab cov ntaub ntawv tsis sib xws?
Kev sib sau cov ntaub ntawv yog sau thiab sau cov ntaub ntawv; kom disaggregate cov ntaub ntawv yog rhuav tshem cov ntaub ntawv sib sau ua ke rau hauv cov khoom siv lossis cov ntaub ntawv me me
Dab tsi yog qhov txawv ntawm cov ntaub ntawv hom thiab qhov sib txawv?
Ib qho kev sib txawv yuav tsum muaj cov ntaub ntawv sib txuas nrog nws, piv txwv li nws tuaj yeem muaj cov ntaub ntawv xws li cov lej, lej lej, cov cim thiab lwm yam. Qhov sib txawv ntawm hom Integer khaws cov lej suav thiab tus cim typevariable khaws cov cim tus nqi. Thawj qhov sib txawv ntawm ntau hom ntaub ntawv yog lawv qhov loj me me
Dab tsi yog qhov sib txawv ntawm qhov ntsuas qhov ntsuas thiab qhov ntsuas thib ob?
Primary index: nyob rau hauv ib tug sequentially order file, qhov Performance index uas nws search key qhia cov sequential order ntawm cov ntaub ntawv. Kuj hu ua clustering index. Secondary index: ib qho Performance index uas nws qhov tseem ceeb tshawb nrhiav qhia qhov kev txiav txim sib txawv ntawm qhov kev txiav txim ntawm cov ntaub ntawv. Kuj hu ua non-clustering index