Vim li cas koj thiaj li xav tau txoj hauv kev database dua li kev ua cov ntaub ntawv ib txwm muaj?
Vim li cas koj thiaj li xav tau txoj hauv kev database dua li kev ua cov ntaub ntawv ib txwm muaj?

Video: Vim li cas koj thiaj li xav tau txoj hauv kev database dua li kev ua cov ntaub ntawv ib txwm muaj?

Video: Vim li cas koj thiaj li xav tau txoj hauv kev database dua li kev ua cov ntaub ntawv ib txwm muaj?
Video: Leng Yang - Yog Vim Dab Tsi (Official Full Song | Nkauj Tawm Tshiab) 2020/05/24 2024, Tej zaum
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Qhov zoo ntawm DBMS ntawm cov ntaub ntawv system

Ob peb ntawm lawv yog raws li nram no: Tsis muaj redundant cov ntaub ntawv : Redundancy tshem tawm los ntawm cov ntaub ntawv normalization. Tsis muaj cov ntaub ntawv duplication txuag cia thiab txhim kho lub sijhawm nkag mus. Yooj yim nkag mus cov ntaub ntawv – Database systems tswj cov ntaub ntawv nyob rau hauv xws li ib txoj kev kom tus cov ntaub ntawv yooj yim nkag tau nrog lub sij hawm teb ceev.

Ntawm no, dab tsi yog qhov zoo ntawm kev tswj cov ntaub ntawv mus rau hauv txoj kev ua cov ntaub ntawv?

Qee qhov zoo ntawm kev siv database muaj xws li cov ntaub ntawv zoo ib yam, yoog raws, kev tswj xyuas yooj yim cov ntaub ntawv kev ruaj ntseg thiab kev ceev ntiag tug thiab txo lub sij hawm txhim kho daim ntawv thov.

Ib yam li ntawd, ua li cas cov ntaub ntawv ib txwm ua txawv ntawm cov ntaub ntawv mus kom ze? Cov txawv nruab nrab ua ntaub ntawv thov system thiab database tswj qhov system yog raws li nram no: A ua ntaub ntawv thov system yog ib phau ntawm cov kev pab cuam uas khaws thiab tswj cov ntaub ntawv hauv computer hard disk. Kev ua ntaub ntawv system tsis muab cov ntaub ntawv sib xws, whereas dbms ua muab cov ntaub ntawv sib xws los ntawm normalization.

Kuj nug, dab tsi yog qhov zoo ntawm cov ntaub ntawv raws li qhov system?

Qhov zoo ntawm Cov Ntaub Ntawv - taw qhia qhov system : Nws tuaj yeem siv ceev thiab tsis siv neeg rov qab ntawm cov ntaub ntawv khaws cia hauv cov ntaub ntawv ntawm lub computer- raws li systems . lub computer tshuab muab kev ua haujlwm los ua haujlwm rau lub hom phiaj no.it kuj tseem tuaj yeem tsim kho cov ntawv thov tshwj xeeb rau lub hom phiaj no.

Dab tsi yog teeb meem nrog kev ua cov ntaub ntawv ib txwm muaj?

Teeb meem tshwm sim los ntawm tsoos ntaub ntawv ib puag ncig muaj xws li: Data redundancy: duplicate cov ntaub ntawv nyob rau hauv ntau yam cov ntaub ntawv , ua rau cov ntaub ntawv tsis sib xws, cov nqi sib txawv siv rau tib tus cwj pwm. Program-data dependency: Hloov cov kev pab cuam uas yuav tsum tau hloov cov ntaub ntawv. Tsis yooj yim.

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