Cov txheej txheem:
Video: SQL query tuning yog dab tsi?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
SQL Tuning los yog SQL optimization . SqlStatements yog siv los muab cov ntaub ntawv los ntawm database. Peb tuaj yeem tau txais cov txiaj ntsig zoo ib yam los ntawm kev sau ntawv sib txawv sql lus . Tab sis siv qhov zoo tshaj plaws nug yog qhov tseem ceeb thaum kev ua tau zoo raug txiav txim siab. Yog li koj yuav tsum tau sql query tuning raws li qhov yuav tsum tau muaj.
Yog li ntawd, dab tsi yog tuning hauv SQL?
Txog SQL Tuning SQL tuning yog cov txheej txheem rov txhim kho SQL ntawv nqe lus ua tau zoo kom ua tau raws li cov hom phiaj tshwj xeeb, ntsuas tau, thiab ua tiav tau. SQL tuning implies kho cov teeb meem indeployed applications. Hauv qhov sib piv, daim ntawv thov tsim teeb tsa cov kev nyab xeeb thiab cov hom phiaj ua haujlwm ua ntej xa cov ntawv thov.
Tsis tas li, kuv yuav ua li cas kuv cov lus nug SQL khiav nrawm dua? 10 Txoj Kev Txhim Kho SQL Query Performance
- Tsis txhob sib koom ntau yam hauv ib lo lus nug.
- Tshem tawm Cursors los ntawm Cov Lus Nug.
- Tsis txhob siv cov lus nug tsis cuam tshuam nrog Scalar Sub Query.
- Tsis txhob muaj ntau nqe lus Table Valued Functions (TVFs)
- Tsim thiab siv Index.
- Nkag siab cov ntaub ntawv.
- Tsim ib qho Kev Xaiv Zoo Tshaj Plaws.
- Muab ib kab hauv ib qho Index.
Ib yam li ntawd, koj tuaj yeem nug, Kuv yuav kho qhov kev nug SQL li cas?
8 Txoj Kev Ua Kom Zoo Kho Koj Cov Lus Nug SQL (rau cov ntaub ntawv tsim khoom)
- Txhais cov kev cai ua lag luam ua ntej pib.
- Txhais SELECT teb tsis yog SELECT *
- Xaiv ntau thaj chaw kom tsis txhob SELECT DISTINCT.
- Tsim kev koom nrog INNER JOIN es tsis yog qhov twg.
- Siv qhov twg los ntawm HAVING los txhais cov ntxaij lim dej.
- Siv wildcards tom kawg ntawm ib kab lus nkaus xwb.
- Siv LIMIT los ua piv txwv cov lus nug.
Dab tsi yog database kev ua tau zoo tuning?
Database tuning piav qhia txog ib pawg ntawm kev ua ub no siv los ua kom zoo thiab homogenize kev ua tau zoo ntawm a database . Database tuning Lub hom phiaj kom siv cov peev txheej hauv lub cev kom ua haujlwm tau zoo thiab ua tau sai.
Pom zoo:
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