Dab tsi yog cov neeg siv txhais cov lus hauv SQL Server?
Dab tsi yog cov neeg siv txhais cov lus hauv SQL Server?

Video: Dab tsi yog cov neeg siv txhais cov lus hauv SQL Server?

Video: Dab tsi yog cov neeg siv txhais cov lus hauv SQL Server?
Video: Kev Muag Khoom thiab Kev Sib Cuam Tshuam Nrog Cov Neeg Qhua Yam Muaj Kev Nyab Xeeb 2024, Kaum ib hlis
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SQL Server muab cov Tus neeg siv txhais cov lus hom raws li ib txoj kev los tsim ib tug pre- txhais temp rooj . Tsis tas li ntawd, vim lawv yog a txhais cov khoom hauv ib lub database, koj tuaj yeem hla lawv ib puag ncig raws li qhov tsis muaj lossis hloov pauv los ntawm ib qho lus nug mus rau lwm qhov. Lawv tuaj yeem nyeem tau tsuas yog cov kev nkag mus rau cov txheej txheem khaws cia.

Ib yam li ntawd, dab tsi yog tus neeg siv txhais lub rooj hom?

Cov neeg siv - cov lus txhais sawv cev cov ntaub ntawv tabular. Lawv raug siv los ua qhov tsis muaj thaum koj dhau cov ntaub ntawv tabular rau hauv cov txheej txheem khaws cia lossis neeg siv - txhais muaj nuj nqi. Cov neeg siv - cov lus txhais tsis tuaj yeem siv los sawv cev kab hauv ib lub database rooj . Cov neeg siv - txhais lus hom tsis tuaj yeem hloov pauv tom qab lawv tsim.

Qhov thib ob, tus neeg siv txhais hom yog dab tsi? A neeg siv - txhais cov ntaub ntawv hom (UDT) yog cov ntaub ntawv hom uas tau muab los ntawm cov ntaub ntawv uas twb muaj lawm hom . Koj tuaj yeem siv UDTs los txuas ntxiv cov built-in hom twb muaj thiab tsim koj tus kheej cov ntaub ntawv customized hom.

Qhov sib thooj, dab tsi yog cov neeg siv txhais hom hauv SQL?

Cov neeg siv - txhais cov ntaub ntawv hom yog nyob ntawm cov ntaub ntawv system hom hauv Microsoft SQL ntawv Server. Cov neeg siv - txhais cov ntaub ntawv hom tuaj yeem siv tau thaum ob peb lub rooj yuav tsum khaws tib yam hom ntawm cov ntaub ntawv nyob rau hauv ib kem thiab koj yuav tsum xyuas kom meej tias cov kab no muaj raws nraim tib cov ntaub ntawv hom , length, thiab NULLability.

Dab tsi yog hom lus hauv SQL?

Cov neeg siv tau txhais hom rooj cia koj hla a rooj raws li qhov parameter rau cov txheej txheem khaws cia los hloov kho cov ntaub ntawv. Siv nws yooj yim, ruaj ntseg, thiab tsis cuam tshuam rau kev ua haujlwm ntawm cov ntaub ntawv. Nyob rau hauv yav dhau los versions ntawm SQL ntawv Neeg rau zaub mov, yog tias kuv xav tau hloov kho ntau kab ntawm cov ntaub ntawv, kuv siv ib ntus rooj.

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