Video: Dab tsi yog qhov clause hauv Oracle?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Cov Oracle Nyob qhov twg Clause yog siv los txwv cov kab rov qab los ntawm cov lus nug. Tsis zoo li cov Oracle SELECT thiab FROM nqe lus, uas tsim nyog rau kev tsim cov lus nug SQL siv tau, cov Oracle Nyob qhov twg lus yog xaiv tau. Cov lus nug SQL tuaj yeem ua haujlwm zoo nrog lossis tsis muaj Oracle Nyob qhov twg lus.
Ib sab ntawm qhov no, dab tsi yog qhov clause hauv SQL?
Ib qhov twg clause hauv SQL qhia tias a SQL ntawv Data Manipulation Language (DML) nqe lus yuav tsum tsuas yog cuam tshuam cov kab uas ua tau raws li cov txheej txheem teev tseg. Hauv luv luv SQL ntawv Nyob qhov twg lus yog siv los rho tawm tsuas yog cov txiaj ntsig los ntawm a SQL lus , xws li: SELECT, INSERT, UPDATE, lossis DELETE nqe lus.
Cov ntaub ntawv tuaj yeem siv rau qhov twg clause hauv Oracle? Oracle CAS kev qhia tso cai rau koj ntxiv yog-lwm cov lus qhia rau SQL nqe lus yam tsis tas yuav hu rau tus txheej txheem. Piv txwv li, koj siv tau tus CAS qhia hauv nqe lus xws li SELECT, UPDATE, lossis DELETE, thiab hauv cov lus xws li SELECT, SIV, HAV, thiab ORDER BY.
Tib neeg kuj nug, dab tsi yog ib nqe lus hauv Oracle?
Hauv Oracle , YOG Clause yog siv nrog GROUP BY Clause txwv cov pab pawg ntawm cov kab rov qab uas qhov xwm txheej yog TRUE.
Qhov kos npe (+) txhais li cas hauv Oracle SQL nyob qhov twg?
Oracle sab nraud koom nrog tus neeg teb xov tooj (+) tso cai rau koj los ua kev sib koom ua ke ntawm ob lossis ntau lub rooj. Piv txwv ceev: -- Xaiv tag nrho cov kab ntawm lub nroog cov lus txawm tias tsis muaj kab sib luag hauv cov nroog cov lus SELECT cov nroog.
Pom zoo:
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