Video: Dab tsi yog qhov txawv ntawm schema thiab database hauv MySQL?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Hauv MySQL , schema yog synonymous nrog database . Logical qauv siv tau los ntawm cov schema khaws cov ntaub ntawv thaum nco tivthaiv yuav siv tau los ntawm lub database khaws cov ntaub ntawv. Kuj, a schema yog collection of tables thaum a database yog ib phau ntawm schema.
Tom qab ntawd, ib tug kuj yuav nug, dab tsi yog qhov txawv ntawm ib tug schema thiab ib tug database?
A database yog lub thawv loj, nws muaj cov ntaub ntawv thiab cov ntaub ntawv teev cia, thiab tag nrho cov schemas hauv nws. Youalways thaub qab a database , nws yog ib tug discrete unit ntawm nws tus kheej. Schemas zoo li folders hauv ib database , thiab feem ntau yog siv los pab pawg cov khoom siv logical ua ke, uas ua rau yooj yim ntawm kev tso cai los ntawm schema.
Tom qab ntawd, lo lus nug yog, dab tsi yog schemas hauv MySQL? Cov mysql schema yog qhov system schema . Nws muaj cov rooj uas khaws cov ntaub ntawv xav tau los ntawm MySQL server raws li nws khiav. Ib tug dav categorization yog qhov mysqlschema muaj cov ntaub ntawv phau ntawv txhais lus cov rooj uas khaws cov databaseobject metadata, thiab cov lus siv rau lwm yam kev ua haujlwm.
Ntawm no, dab tsi yog qhov schema ntawm lub database?
Lub sij hawm " schema " hais txog lub koom haum ntawm cov ntaub ntawv raws li daim ntawv qhia txog yuav ua li cas cov database yog tsim (sib faib ua database rooj nyob rau hauv rooj plaub ntawm kev sib raug zoo databases ). Lub ntsiab txhais ntawm a databaseschema yog ib txheej ntawm cov qauv (cov kab lus) hu ua integrityconstraints imposed rau a database.
Dab tsi yog qhov txawv ntawm schema thiab database hauv Oracle?
Hauv Oracle , cov neeg siv thiab schemas yog qhov tseem ceeb tib yam. Koj tuaj yeem xav tias tus neeg siv yog tus account koj siv los txuas rau a database , thiab a schema yog cov khoom (cov ntxhuav, views, thiab lwm yam) uas nyob rau hauv tus account. Tab sis siv dbca ( database creationassistant) yooj yim pib.
Pom zoo:
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