Cov txheej txheem:
Video: Dab tsi yog qhov tsim qauv tsim qauv tsim thiab lub cev database tsim?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Logical database qauv muaj xws li; ERD, daim duab ua lag luam, thiab cov ntaub ntawv tawm tswv yim rau cov neeg siv; hos lub cev database qauv muaj xws li; server model diagram, tsim database cov ntaub ntawv, thiab cov neeg siv cov lus teb cov ntaub ntawv.
Raws li txoj cai, qhov kev tsim cov ntaub ntawv tsim nyog yog dab tsi?
Logical database tsim yog tus txheej txheem ntawm kev txiav txim siab yuav ua li cas npaj cov yam ntxwv ntawm cov koom haum hauv ib puag ncig kev lag luam muab rau hauv database cov qauv, xws li cov rooj ntawm kev sib raug zoo database.
Tsis tas li ntawd, dab tsi yog txhais los ntawm kev tsim database? Database tsim yog lub koom haum ntawm cov ntaub ntawv raws li a database qauv. Cov tus tsim txiav txim siab seb cov ntaub ntawv twg yuav tsum tau muab khaws cia thiab yuav ua li cas cov ntaub ntawv sib cuam tshuam. Database tsim suav nrog kev faib cov ntaub ntawv thiab txheeb xyuas kev sib txheeb. Qhov no theoretical sawv cev ntawm cov ntaub ntawv yog hu ua ib tug ontology.
Nyob rau hauv no hais txog, dab tsi yog lub logic tsim thiab lub cev tsim?
Logical tsim deals nrog cov logical kev sib raug zoo ntawm cov khoom. Qhov chaw-kev sib raug zoo (ER) qauv qauv tuaj yeem siv rau logical tsim ntawm cov ntaub ntawv warehouse. ER qauv muaj xws li kev txheeb xyuas cov chaw (cov khoom tseem ceeb), cov yam ntxwv (cov khoom ntawm cov khoom) thiab kev sib raug zoo ntawm lawv.
Koj tsim ib lub database li cas?
Tus txheej txheem tsim muaj cov kauj ruam hauv qab no:
- Txiav txim siab lub hom phiaj ntawm koj lub database.
- Nrhiav thiab teeb tsa cov ntaub ntawv xav tau.
- Muab cov ntaub ntawv faib ua cov rooj.
- Tig cov ntaub ntawv rau hauv kab.
- Qhia cov yuam sij tseem ceeb.
- Teeb tsa cov rooj sib tham.
- Kho koj tus qauv tsim.
- Siv cov kev cai normalization.
Pom zoo:
Dab tsi yog qhov txawv ntawm cov khoom taw qhia cov qauv database thiab cov qauv kev sib raug zoo?
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