Dab tsi yog delimiter hauv cov txheej txheem khaws cia?
Dab tsi yog delimiter hauv cov txheej txheem khaws cia?

Video: Dab tsi yog delimiter hauv cov txheej txheem khaws cia?

Video: Dab tsi yog delimiter hauv cov txheej txheem khaws cia?
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Koj txhais a DELIMITER qhia rau tus neeg siv mysql los kho cov nqe lus, kev ua haujlwm, cov txheej txheem khaws cia los yog ua raws li tag nrho cov lus. Nquag hauv ib. sql ntaub ntawv koj teem ib tug txawv DELIMITER zoo li $$. Cov DELIMITER hais kom ua yog siv los hloov tus qauv tus lej ntawm MySQL cov lus txib (piv txwv li;).

Tsis tas li ntawd, kev siv delimiter hauv kev khaws cia yog dab tsi?

Delimiters tuaj yeem yog siv thaum koj yuav tsum tau txhais cov cov txheej txheem khaws cia , muaj nuj nqi raws li tau zoo raws li tsim triggers. Lub neej ntawd tus lej yog semicolon. Koj tuaj yeem hloov qhov tus lej tsim cov txheej txheem thiab lwm yam.

Tom qab ntawd, lo lus nug yog, dab tsi yog tus txhais hauv cov txheej txheem khaws cia? Tag nrho khaws cia cov kev pab cuam ( cov txheej txheem , functions, and triggers) and views can have a DEFINER tus cwj pwm uas hu ua MySQL account. Yog tias DEFINER tus cwj pwm raug tshem tawm los ntawm a khaws cia program lossis saib cov ntsiab lus, lub neej ntawd tus account yog tus neeg siv uas tsim cov khoom.

Yog li ntawd, dab tsi yog delimiter hauv SQL?

Hauv kev tswj hwm database peb xav kom tsim cov ntaub ntawv ntawm cov ntaub ntawv khaws cia hauv DBMS rau ntau lub hom phiaj. Cov tus lej yog tus cwj pwm hauv SQL ntawv uas yog siv los cais cov ntaub ntawv cov khoom hauv ib lub database. Nws txheeb xyuas qhov pib thiab qhov kawg ntawm txoj hlua cim.

MySQL txheej txheem yog dab tsi?

A txheej txheem yog ib tug subroutine (xws li ib tug subprogram) nyob rau hauv ib tug tsis tu ncua scripting lus, khaws cia nyob rau hauv ib tug database. Nyob rau hauv cov ntaub ntawv ntawm MySQL , cov txheej txheem tau sau rau hauv MySQL thiab khaws cia rau hauv MySQL database / server. A MySQL txheej txheem muaj lub npe, ib daim ntawv teev npe, thiab SQL nqe lus.

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