Cov txheej txheem:
Video: Dab tsi yog hom ntaub ntawv hauv PL SQL?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
PL/SQL muaj ob hom ntaub ntawv hom: scalar thiab composite. Cov hom scalar yog hom uas khaws ib qho txiaj ntsig xws li tus lej, Boolean , tus cwj pwm , thiab datetime whereasthe composite types yog hom uas khaws ntau qhov tseem ceeb, piv txwv, sau thiab sau.
Hais txog qhov no, dab tsi yog hom ntaub ntawv hauv Oracle?
Oracle muab cov ntaub ntawv hauv qab no built-in:
- tus cwj pwm datatypes. CHAR. NCHAR. VARCHAR2 thiab VARCHAR. NVARCHAR2. CLOB. NCLOB. LONG.
- NUMBER datatype.
- DATE datatype.
- binary datatypes. BLOB. BFILE. RAW. LONG RAW.
Tom qab ntawd, lo lus nug yog, dab tsi yog cov ntaub ntawv sib txawv uas tuaj yeem txhais tau hauv PL SQL thaiv? PL / SQL ntawv muab ntau predefined hom ntaub ntawv . Piv txwv li, koj ua tau xaiv los ntawm tus lej, ntab taw tes, cim, BOOLEAN, hnub tim, sau, siv, thiab khoom loj (LOB) hom.
Hais txog qhov no, koj txhais li cas los ntawm hom ntaub ntawv?
Hauv computer science thiab computer programming, a hom ntaub ntawv los yog yooj yim hom yog tus cwj pwm ntawm cov ntaub ntawv uas qhia lub compiler lossis tus neeg txhais lus li cas tus programmer npaj siab yuav siv cov ntaub ntawv . Qhov no hom ntaub ntawv txhais cov haujlwm uas tuaj yeem ua tiav ntawm qhov cov ntaub ntawv , lub ntsiab lus ntawm cov ntaub ntawv , thiab txoj kev muaj nuj nqis ntawm qhov ntawd hom tuaj yeem khaws cia.
Dab tsi yog hom ntaub ntawv hauv SQL?
Hauv tsab xov xwm no A hom ntaub ntawv yog tus cwj pwm uas qhia txog qhov hom ntawm cov ntaub ntawv uas cov khoom yuav tuav tau: integer cov ntaub ntawv , tus cwj pwm cov ntaub ntawv , nyiaj txiag cov ntaub ntawv , hnub thiab sijhawm cov ntaub ntawv , binary hlua, thiab lwm yam. SQL ntawv Serversupplies ib txheej ntawm system hom ntaub ntawv uas txhais tag nrho cov hom ntawm cov ntaub ntawv uas tuaj yeem siv nrog SQL ntawv Server.
Pom zoo:
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