Video: Peb puas tuaj yeem hloov kho qhov pom hauv Oracle?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Teb: A SAIB hauv Oracle yog tsim los ntawm joiningone los yog ntau lub rooj. Thaum koj hloov tshiab record(s) hauv a SAIB , nws tshiab cov ntaub ntawv nyob rau hauv lub hauv paus tablestate ua li Saib . Yog li, yog, koj tuaj yeem hloov kho thedata hauv ib Oracle VIEW muab koj muaj cai tsim nyog rau lub hauv paus Oracle rooj.
Tsis tas li ntawd, kev saib puas tuaj yeem hloov kho hauv Oracle?
Saib hauv Oracle tuaj yeem hloov kho tau raws li cov xwm txheej tshwj xeeb. Nws ua tau yuav ua kom yuam kev, thiab feem ntau yog tsis advisable. Ib updataable saib yog ib koj ua tau siv los ntxig, hloov tshiab , los yog rho tawm cov kab lus hauv qab. Txhua kab hauv lub saib yuav tsum tau daim ntawv qhia rau ib kem ntawm ib lub rooj.
Ib yam li ntawd, peb puas tuaj yeem ua DML cov haujlwm ntawm kev pom hauv Oracle? Tsuas yog cov lus xaiv tau muab khaws cia rau hauv database hloov. Txawm li cas los xij, views tau siv tau thiab ua DMLoperations (Ntxig, Hloov Kho & Rho tawm) thiab. Koj ua tau ntxig cov ntaub ntawv rau cov lus saum toj no siv lub kev xav nyuam qhuav tsim. Thiab nws yog tib syntax uas peb siv los ntxig cov ntaub ntawv rau cov ntxhuav.
Cov lus nug tseem yog, peb tuaj yeem hloov kho qhov pom?
Kev txwv rau Hloov kho Cov ntaub ntawv los ntawm Views. Yog saib muaj kev sib koom ntawm ntau lub rooj, koj tuaj yeem tsuas ntxig thiab update ib table hauv saib , thiab koj ua tau tsis rho tawm kab. Koj ua tau ' tsis ncaj qha hloov cov ntaub ntawv hauv kev pom raws li cov lus nug ntawm lub koomhaum. Koj ua tau 'tsis hloov cov ntaub ntawv hauv kev pom uas siv GROUP BY lossis DISTINCT nqe lus.
Koj puas tuaj yeem ntxig cov ntaub ntawv rau hauv qhov pom?
1 Teb. Yog tias koj siv cov khoom siv sab hauv, thiab koj saib muaj tag nrho cov kab hauv cov rooj hauv paus, tom qab ntawd koj saib tej zaum yuav updataable. Txawm li cas los xij, rau ntau-tableupdataable saib , INSERT tuaj yeem ua haujlwm yog tias nws ntxig rau hauv ib lub rooj. Koj tuaj yeem faib koj ntxig kev ua haujlwm ntau INSERT nqe lus.
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