Video: Dab tsi yog denormalization hauv database nrog piv txwv?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Denormalization hauv Databases . Denormalization yog ib tug database optimization txheej txheem uas peb ntxiv cov ntaub ntawv redundant rau ib los yog ntau tshaj rooj . Rau Piv txwv li, nyob rau hauv ib tug normalized database , peb yuav muaj Kev Kawm rooj thiab ib tug Xib Hwb rooj . Txhua qhov kev nkag hauv Chav Kawm yuav khaws tus xibfwb qhia ntawv rau Chav Kawm tab sis tsis yog tus xibfwb qhia npe.
Ntxiv mus, dab tsi yog denormalization nyob rau hauv ib tug database?
Denormalization yog ib lub tswv yim uas database cov thawj coj siv los nce kev ua haujlwm ntawm a database infrastructure. Nws suav nrog ntxiv cov ntaub ntawv rov ua dua mus rau qhov normalized database kom txo tau tej yam teeb meem nrog database queries uas muab cov ntaub ntawv los ntawm ntau lub rooj rau hauv ib lub rooj.
Tsis tas li ntawd, vim li cas peb thiaj xav tau denormalization hauv database? Denormalization yog ib lub tswv yim siv rau yav dhau los-normalized database nce kev ua tau zoo. Lub tswv yim tom qab nws yog ntxiv cov ntaub ntawv rov ua dua qhov twg peb xav tias nws yuav pab tau peb tshaj plaws. Peb tuaj yeem siv cov cwj pwm ntxiv hauv ib lub rooj uas twb muaj lawm, ntxiv cov rooj tshiab, lossis tseem tsim cov rooj zaum uas twb muaj lawm.
Ib yam li ntawd, tib neeg nug, qhov piv txwv ntawm cov ntaub ntawv yog dab tsi?
Microsoft Excel spreadsheet lossis Microsoft Access yog qhov zoo piv txwv ntawm desktop database cov kev pab cuam. Cov kev pabcuam no tso cai rau cov neeg siv nkag mus rau cov ntaub ntawv, khaws cia, tiv thaiv nws, thiab khaws nws thaum xav tau. Lawv suav nrog databases zoo li SQL Server, Oracle Database , Sybase, Informix, thiab MySQL.
Qhov zoo ntawm denormalization yog dab tsi?
Denormalization tuaj yeem txhim kho kev ua tau zoo los ntawm: Txo qhov xav tau ntawm kev koom nrog. Precomputing aggregate qhov tseem ceeb, uas yog, xam lawv ntawm cov ntaub ntawv hloov lub sij hawm, es tsis yog nyob rau lub sij hawm xaiv. Txo tus naj npawb ntawm cov ntxhuav, qee zaum.
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