Cov txheej txheem:

Koj nkag siab dab tsi los ntawm cov txheej txheem ntau yam?
Koj nkag siab dab tsi los ntawm cov txheej txheem ntau yam?

Video: Koj nkag siab dab tsi los ntawm cov txheej txheem ntau yam?

Video: Koj nkag siab dab tsi los ntawm cov txheej txheem ntau yam?
Video: Saib Mis paub Poj niam (hluas nkauj) tus yam ntxwv lub siab 2024, Kaum ib hlis
Anonim

Multiversion Concurrency Control. Multiversion Concurrency Control (MVCC) yog ib txoj hauv kev los tswj qhov sib xws ntawm cov ntaub ntawv nkag los ntawm ntau cov neeg siv concurrently. MVCC siv lub snapshot rho tawm lav uas ua kom ntseeg tau tias txhua qhov kev sib pauv ib txwm pom cov ntaub ntawv zoo ib yam.

Yog li, dab tsi yog cov txheej txheem tswj hwm kev sib koom ua ke?

Lub kaw lus tswj hwm kev sib koom ua ke tuaj yeem siv ib-theem lossis ob-theem locking raws tu qauv

  • 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.

Tsis tas li ntawd, Multiversion schemes hauv DBMS yog dab tsi? Abstract. Concurrency tswj tswv yim siv ntau lub versions ntawm cov ntaub ntawv khoom yog nthuav tawm uas tso cai rau nce concurrency. Cov tswv yim muab qhov tsim nyog version rau txhua qhov kev thov nyeem. Kev ua lag luam muab cov ntawv thov uas tuaj yeem rhuav tshem cov ntaub ntawv ncaj ncees raug rho tawm.

Tsis tas li ntawd, dab tsi yog kev tswj hwm kev tswj hwm hauv DBMS?

Concurrency tswj yog tus txheej txheem hauv DBMS rau kev tswj hwm kev ua haujlwm ib txhij tsis muaj kev sib cav sib ceg. Kev nkag mus tau yooj yim heev yog tias txhua tus neeg siv tsuas yog nyeem cov ntaub ntawv. Concurrency tswj yog siv los daws cov kev tsis sib haum xeeb uas feem ntau tshwm sim nrog ntau tus neeg siv.

Multi Version Concurrency Control hauv postgresql yog dab tsi?

MVCC, uas sawv cev rau multiversion concurrency tswj , yog ib qho ntawm cov txheej txheem tseem ceeb Postgres siv los ua kev lag luam. MVCC tso Postgres khiav ntau cov lus nug uas kov tib kab ib txhij, thaum khaws cov lus nug cais tawm ntawm ib leeg.

Pom zoo: