Cov txheej txheem:
- Cov tswv yim pom zoo siv rau dab tsi?
- Vim li cas thiaj siv cov khoom pom tsis yog lub rooj?
- Dab tsi yog materialized saib?
- Dab tsi yog qhov txawv ntawm qhov pom thiab pom qhov khoom siv?
Video: Leej twg invented materialized view?
2024 Tus sau: Fiona Howard | [email protected]. Kawg hloov kho: 2024-01-10 06:38
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.
Pom zoo:
Leej twg invented chorded keyboard?
Lub Kaum Ob Hlis 1968, Douglas C. Engelbart tau qhia lub ntiaj teb rau ob lub khoos phis tawj tshiab tshiab ntawm nws tus kheej tsim . Yuav muaj pes tsawg tus yuam sij chorded keyboard? Chording keyboards kuj tau siv los ua cov khoom siv tau yooj yim tab sis ob txhais tes tawm tswv yim rau qhov tsis pom kev (xws li ua ke nrog lub ntsej muag zoo nkauj lossis lub suab sib txuas).
Leej twg invented ius sanguinis?
Ius sanguinis yog ib qho kev lig kev cai niaj hnub tsim los ntawm Fabkis, thiab nws tau nthuav dav thoob plaws teb chaws Europe thaum lub sijhawm cuaj-xyoo pua . Yog USA jus soli or jus sanguinis? Lwm txoj kev hu ua jus sanguinis yog thaum ib tug neeg tau txais kev ua pej xeem los ntawm lawv niam lawv txiv lossis poj koob yawm txwv.
Leej twg invented lub mesmerise?
Lo lus "mesmerize" hnub rov qab mus rau xyoo pua 18th Austrian kws kho mob hu ua Franz Anton Mesmer (1734-1815). Nws tsim ib txoj kev xav ntawm kev mob uas cuam tshuam nrog lub zog sib nqus, uas nws hu ua tsiaj magnetism. (Nws yuav tom qab ntawd hu ua mesmerism.
Leej twg invented opposite hnub?
Cov lus tshaj tawm ntxov tshaj plaws rau Hnub Tawm Tsam hnub rov qab mus rau xyoo 1920 thaum Thawj Tswj Hwm Calvin Coolidge tau tshaj tawm tias nws tsis xav mus xaiv tsa . Puas Yog Hnub Kawg tiag? Opposite Day, tseem hu ua National Opposite Day, yog ua kev zoo siab rau Lub Ib Hlis 25 hauv Tebchaws Meskas.
Leej twg invented robotic exoskeleton?
Lub Peb Hlis ntawm Hlau Warriors. Rau tag nrho cov kev kho mob thiab kev lag luam kev vam meej tib neeg exoskeletons cog lus, lawv cov keeb kwm nyob rau hauv ib tug tub rog tshuab hu ua Hardiman. Tsim los ntawm General Electric engineer, Ralph S.
