Yuav ua li cas redundancy tswj hauv dbms?

Cov txheej txheem:

Yuav ua li cas redundancy tswj hauv dbms?
Yuav ua li cas redundancy tswj hauv dbms?
Anonim

Redundancy yog lub tswvyim ntawm kev rov ua dua ntawm cov ntaub ntawv piv txwv li txhua cov ntaub ntawv yuav muaj ntau tshaj li ib daim qauv. … Whereas DBMS tswj redundancy los ntawm tuav ib qho chaw cia ntawm cov ntaub ntawv uas tau txhais ib zaug thiab nkag los ntawm ntau tus neeg siv. Raws li tsis muaj los yog tsawg dua redundancy, cov ntaub ntawv tseem zoo ib yam.

Yuav ua li cas cov ntaub ntawv redundancy tswj hauv DBMS?

A DBMS tuaj yeem txo cov ntaub ntawv rov ua dua thiab tsis sib xws los ntawm kev txo qis cov ntaub ntawv cais uas tib cov ntaub ntawv rov ua dua. DBMS yuav tsis ua kom lub koom haum tshem tawm cov ntaub ntawv redundancy nkaus, tab sis nws tuaj yeem pab tswj kev rov ua dua. … DBMS uncouples cov kev pab cuam thiab cov ntaub ntawv, ua kom cov ntaub ntawv sawv ntawm lawv tus kheej.

Yuav ua li cas peb tiv thaiv cov ntaub ntawv redundancy hauv database?

Dub qhov nkag ntawm cov neeg siv khoom npe suav tias yog cov ntaub ntawv rov ua dua. Txawm hais tias cov ntaub ntawv redundancy tshwm sim hauv database lossis hauv cov ntaub ntawv khaws cia, nws tuaj yeem ua teeb meem. Hmoov zoo, cov ntaub ntawv rov ua dua tuaj yeem pab tiv thaiv cov ntaub ntawv rov ua dua los ntawm kev khaws cov ntaub ntawv tib yam hauv ntau qhov chaw.

Yuav ua li cas tswj redundancy?

Controlled Redundancy yog txheej txheem los siv cov teb tsis tu ncua hauv cov ntaub ntawv lub cev txhawm rau txhawm rau nyeem ntawvdatabase nkag.

Vim li cas thiaj li tswj tau rov ua dua?

Kev tswj tsis tau rov ua dua yog cov txheej txheem tsim nyog siv cov khoom siv rov ua dua hauv cov ntaub ntawv. Qhov no ua kom cov ntaub ntawv nkag mus sai thiab tseem txhim kho kev ua haujlwm ntawm cov lus nug. Feem ntau, DBMS ua kom muaj kev faib cov ntaub ntawv hauv cov ntaub ntawv.

Pom zoo:

Nthuav cov khoom
Lub sijhawm elongation ntawm kev txhais lus uncharged trnas txav mus rau?
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Lub sijhawm elongation ntawm kev txhais lus uncharged trnas txav mus rau?

Peptide daim ntawv cog lus; uncharged tRNA txav mus rau qhov E site & tom qab tawm ntawm ribosome; lub mRNA tau hloov pauv 3 lub hauv paus mus rau sab laug, ua rau tRNA bearing dipeptide hloov mus rau P site P site P-site (rau peptidyl) yog qhov thib ob khi qhov chaw rau tRNA hauv ribosome.

Dab tsi yog asbestiform fibers?
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Dab tsi yog asbestiform fibers?

Raws li siv hauv daim ntawv tshaj tawm no, lo lus asbestiform fibers suav nrog fibers uas muaj lub zog zoo thiab yoog raws, ruaj khov, cov qauv saum npoo tsis muaj qhov tsis xws luag, thiab ntau lwm yam khoom tau piav qhia tom qab. Kev lag luam zoo asbestos yog ib qho piv txwv ntawm asbestiform fiber.

Colleen dewhurst tuag li cas?
Nyeem ntxiv

Colleen dewhurst tuag li cas?

Dewhurst tuag rau hnub Thursday ntawm mob qog noj ntshav ntawm nws lub tsev hauv New York suburb ntawm Lewisboro, hais Tom Viola, tus kws tshaj lij rau lub koomhaum uas nws ua haujlwm, Tus Ua Yeeb Yam Equity. Txawm hais tias ntau phau ntawv sau npe Dewhurst hnub nyoog li 65, nws yog 67, hais tias nws tus khub ntev, Ken Marsolais.