Cov txheej txheem:
Video: Dab tsi yog synonym hauv SQL nrog piv txwv?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Kev piav qhia. A lub ntsiab lus yog lwm lub npe rau cov khoom xws li rooj, views, sequences, khaws cia cov txheej txheem, thiab lwm yam khoom siv database. Koj feem ntau siv cov ntsiab lus thaum koj tso cai nkag mus rau ib qho khoom los ntawm lwm lub schema thiab koj tsis xav kom cov neeg siv yuav tsum txhawj xeeb txog kev paub txog qhov twg schema yog tus tswv ntawm cov khoom.
Ib yam li ntawd, kuv yuav ua li cas los tsim ib lub ntsiab lus hauv SQL?
Siv SQL Server Management Studio
- Hauv Object Explorer, nthuav cov ntaub ntawv uas koj xav tsim koj qhov kev pom tshiab.
- Right-click the Synonyms folder, ces nyem New Synonym.
- Hauv Add Synonym dialog box, sau cov ntaub ntawv hauv qab no. Synonym npe. Ntaus lub npe tshiab koj yuav siv rau cov khoom no. Synonym schema.
Ib tug kuj yuav nug, dab tsi yog qhov kev siv qhov ntsuas hauv SQL? Ib qhov ntsuas yog siv los ua kom cov kev ua tau zoo ntawm cov lus nug. Nws ua qhov no los ntawm kev txo tus naj npawb ntawm cov nplooj ntawv database cov ntaub ntawv uas yuav tsum tau mus xyuas / scanned. Hauv SQL ntawv Server, ib pawg qhov ntsuas txiav txim lub cev kev txiav txim ntawm cov ntaub ntawv nyob rau hauv ib lub rooj. Tsuas muaj ib pawg xwb qhov ntsuas ib lub rooj (lub clustered qhov ntsuas yog lub rooj).
Tsis tas li ntawd, ob qho laj thawj dab tsi los tsim cov lus sib dhos?
(Xaiv ob .) Koj muaj ntau lub rooj. Koj lub npe rooj ntev dhau lawm. Koj lub rooj muaj cov npe nyuaj.
Dab tsi yog views hauv SQL?
Hauv SQL ntawv , kev pom yog lub rooj virtual raws li qhov tshwm sim-teeb ntawm ib qho SQL ntawv nqe lus. Cov teb hauv kev pom yog cov teb los ntawm ib lossis ntau lub rooj tiag tiag hauv cov ntaub ntawv. Koj tuaj yeem ntxiv SQL ntawv functions, qhov twg, thiab JOIN nqe lus rau ib tug saib thiab nthuav cov ntaub ntawv raws li yog hais tias cov ntaub ntawv yog los ntawm ib lub rooj.
Pom zoo:
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