Video: Dab tsi yog hom ntaub ntawv khaws cia tus nqi Boolean?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Taw qhia rau PostgreSQL Boolean hom
PostgreSQL siv ib qho byte rau khaws cia booleanvalue hauv database. BOOLEAN tuaj yeem sau luv ua BOOL. Instandard SQL, tus nqi Boolean tuaj yeem yog TRUE, FALSE, lossis NULL.
Ib yam li ib tug yuav nug, dab tsi yog datatype los khaws tus nqi Boolean?
Cov BOOLEAN cov ntaub ntawv hom khw muag khoom TRUE lossis FALSE cov ntaub ntawv tus nqi raws li ib tug byte.
Ib sab saum toj no, 0 txhais li cas hauv Boolean? Boolean Kev hloov pauv thiab cov ntaub ntawv hom (lossis tsis muaj qhov ntawd C) C ua tsis muaj boolean hom ntaub ntawv, thiab ib txwm siv cov lej rau boolean kuaj. Zero yog siv rau sawv cev cuav, thiab ib tug yog siv rau sawv cev muaj tseeb. Rau kev txhais lus, Xoom txhais tias yog cuav thiab dab tsi tsis yog xoom yog txhais raws li qhov tseeb. #define cuav 0.
Yog li, hom ntaub ntawv twg yog siv los khaws cov ntaub ntawv tseeb lossis tsis tseeb?
Boolean hom ntaub ntawv . Hauv computer science, theBoolean hom ntaub ntawv yog a hom ntaub ntawv uas muaj ib qho ntawm ob qhov tseem ceeb (feem ntau yog denoted muaj tseeb thiab cuav ), npaj los sawv cev rau ob qhov tseeb Qhov tseem ceeb ntawm logic thiab Boolean algebra.
Dab tsi yog hom ntaub ntawv rau Boolean hauv MySQL?
Raws li ntawm MySQL 5.0.3, IB hom ntaub ntawv yog siv los khaws cov nqi me ntsis. Txwv tsis pub, raws li cov MySQL phau ntawv koj siv tau bool ua thiab boolean uas yog tam sim no aliases ntawm tinyint(1): Bool , Boolean : Cov hom yog synonyms rau TINYINT(1). Avalue ntawm xoom yog suav tias yog cuav.
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