Puas indexes ceev hloov tshiab?

2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47

Index muaj nuj nqis rau inserts, tshiab , thiab deletes. Derby yuav tsum ua ua hauj lwm tswj indexes . Yog koj hloov tshiab ib lub rooj, lub system yuav tsum tswj cov indexes uas yog nyob rau kab kho tshiab . Yog li muaj ntau indexes ua tau ceev ceev xaiv cov nqe lus, tab sis maj mam ntxig ntxig, tshiab , thiab deletes.

Raws li, cov indexes qeeb qeeb hloov tshiab?

1 Teb. Database indexes ua database hloov tshiab qeeb thiab sai dua tib lub sijhawm. Qhov no nyob ntawm tus hloov tshiab nqe lus: Thaum koj muaj hloov tshiab ntawm txhua kab zoo li hloov tshiab mytable set mycolumn = 4711 ces qhov ntsuas creation yuav qeeb tus hloov tshiab , vim nws yog ib co haujlwm ntxiv uas xav tau sijhawm.

Tsis tas li ntawd, indexes cuam tshuam li cas rau kev ua haujlwm ntawm database? Index yog cov qauv ntaub ntawv uas tso cai rau koj xaiv sai thiab txheeb cov kab hauv a database rooj. Piv txwv li, yog tias koj cov ntxhuav feem ntau cuam tshuam los ntawm INSERT, Hloov Kho, lossis DELETE cov lus, ces koj tag nrho kev ua tau zoo poob vim indexes yuav tsum tau hloov kho tom qab cov haujlwm ntawd.

Xav txog qhov no, cov indexes puas cuam tshuam rau kev ua tau zoo ntawm kev hloov tshiab thiab kev ntxig?

Yog, nws kiag li cuam tshuam kev ua haujlwm rau INSERTUPDATE DELETE cov haujlwm. Thaum cov ntaub ntawv tau manipulated, tag nrho cov cuam tshuam indexes yuav tsum xav txog qhov hloov tshiab . Koj tuaj yeem xav txog kev siv ib leeg qhov ntsuas mus rau kev nthuav dav ntawm kev siv ntau cov lus nug.

Puas tuaj yeem ntxiv qhov Performance index qeeb rau cov lus nug?

Ib qho yuam kev index tau ua ib qhov ntsuas tsim rau ntawm kab uas tsis muab cov ntaub ntawv yooj yim dua los yog ib qho qhov ntsuas tsim nyob rau hauv ntau kab uas es tsis txhob speeding lus nug , slows lawv nqes . Ib lub rooj tsis muaj pawg index tau kuj raug suav hais tias yog neeg pluag indexing xyaum.