Video: Vim li cas thiaj xav tau concurrency hauv DBMS?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Yog vim li cas siv Concurrency tswj txoj kev yog DBMS : Txhawm rau siv Isolation los ntawm kev sib cais ntawm kev sib cav sib ceg. Txhawm rau daws teeb meem nyeem-sau thiab sau-sau teeb meem. Lub system yuav tsum tswj kev sib cuam tshuam ntawm cov kev sib pauv hloov pauv.
Hais txog qhov no, dab tsi yog concurrency hauv DBMS?
Cov ntaub ntawv sib npaug txhais tau hais tias ntau tus neeg siv tuaj yeem nkag mus rau cov ntaub ntawv tib lub sijhawm. Cov ntaub ntawv sib xws txhais tau hais tias txhua tus neeg siv pom qhov kev pom zoo ib yam ntawm cov ntaub ntawv, suav nrog kev pom kev hloov pauv los ntawm tus neeg siv khoom lag luam thiab kev lag luam ntawm lwm tus neeg siv.
Tom qab ntawd, lo lus nug yog, dab tsi yog cov txheej txheem tswj kev sib koom ua ke hauv DBMS? Distributed DBMS - Tswj Concurrency
- Ib-theem Xauv raws tu qauv.
- Ob-theem Xauv raws tu qauv.
- Distributed Ob-theem Locking Algorithm.
- Distributed Timestamp Concurrency Control.
- Cov duab tsis sib haum xeeb.
- Distributed Optimistic Concurrency Control Algorithm.
Ntxiv mus, yuav ua li cas concurrency tuav hauv database?
Muaj ntau txoj hauv kev uas qhov teeb meem ntawm sib npaug tuaj yeem daws tau los ntawm a DBMS . Cov txheej txheem tseem ceeb yog: Timestamp ordering: Thaum twg qhov kev sib pauv pib, lub sij hawm tau cuam tshuam nrog nws. Cov kev lag luam tsis sib haum xeeb tau teem sijhawm, thiab tua lossis rho tawm thiab rov pib dua.
Qhov teeb meem concurrency yog dab tsi?
Cov teeb meem sib thooj . Concurrency yog hais txog kev sib koom ntawm cov peev txheej los ntawm ntau tus neeg siv sib tham sib lossis cov ntawv thov kev pab cuam tib lub sijhawm. Tus neeg saib xyuas cov ntaub ntawv tswj hwm qhov kev nkag mus no los tiv thaiv cov teebmeem uas tsis xav tau, xws li: Kev hloov tshiab ploj.
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