Leej twg invented materialized view?

Cov txheej txheem:

Leej twg invented materialized view?
Leej twg invented materialized view?

Video: Leej twg invented materialized view?

Video: Leej twg invented materialized view?
Video: Paradise - Nws Yog Leej Twg Music Video (2002 Official Music Video) 2024, Hlis ntuj nqeg
Anonim

Materialized views tau siv ua ntej los ntawm the Oracle Database: Cov lus nug rov sau dua tshiab tau ntxiv los ntawm version 8i.

Cov tswv yim pom zoo siv rau dab tsi?

Nyob hauv cov ntaub ntawv warehouses, koj tuaj yeem siv cov ntaub ntawv pom rau precompute thiab khaws cov ntaub ntawv sib sau xws li cov khoom muagCov khoom pom hauv cov cheeb tsam no feem ntau hu ua cov ntsiab lus, vim lawv khaws cov ntaub ntawv sau tseg. Lawv tuaj yeem siv los ua precompute koom nrog lossis tsis muaj kev sib sau.

Vim li cas thiaj siv cov khoom pom tsis yog lub rooj?

Cov khoom siv tau pom yog siv los ua kom cov lus nug ua tau zoo vim nws muaj cov txiaj ntsig ntawm cov lus nug. Lawv yuav tsum tau siv rau kev tshaj tawm es tsis txhob ntawm lub rooj kom ua tiav sai.

Dab tsi yog materialized saib?

Ib qhov pom tseeb yog cov ntaub ntawv ua ntej suav tau los ntawm cov lus nug tshwj xeeb (qhov SELECT hauv kev pom txhais) thiab khaws cia rau tom qab siv. Vim hais tias cov ntaub ntawv yog pre-computed, querying ib materialized saib yog sai dua executing ib query tiv thaiv lub hauv paus rooj ntawm saib.

Dab tsi yog qhov txawv ntawm qhov pom thiab pom qhov khoom siv?

Cov khoom siv tau pom yog disk raws thiab tau hloov kho raws sijhawm raws li cov lus nug txhais. Kev saib yog virtual nkaus xwb thiab khiav cov lus nug txhais txhua zaus lawv nkag mus.

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