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Dab tsi yog hom ntaub ntawv hauv SQL?
Dab tsi yog hom ntaub ntawv hauv SQL?

Video: Dab tsi yog hom ntaub ntawv hauv SQL?

Video: Dab tsi yog hom ntaub ntawv hauv SQL?
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SQL Data Type yog tus cwj pwm uas qhia txog qhov hom ntawm cov ntaub ntawv ntawm tej yam khoom. Txhua kem, sib txawv thiab nthuav qhia muaj qhov cuam tshuam hom ntaub ntawv hauv SQL . Koj tuaj yeem siv cov no hom ntaub ntawv thaum tsim koj lub rooj. Koj tuaj yeem xaiv ib hom ntaub ntawv rau ib kab lus raws li koj xav tau.

Ua li no, hom ntaub ntawv siv hauv SQL yog dab tsi?

SQL cov ntaub ntawv hom tuaj yeem muab faib ua ntau pawg hauv qab no

  • Cov ntaub ntawv naj npawb xws li int, tinyint, bigint, ntab, tiag thiab lwm yam.
  • Hnub thiab Lub Sijhawm cov ntaub ntawv xws li Hnub, Lub Sijhawm, Hnub Nyoog thiab lwm yam.
  • Cim thiab hlua cov ntaub ntawv hom xws li char, varchar, ntawv nyeem thiab lwm yam.

Dab tsi yog hom ntaub ntawv hauv database? A hom ntaub ntawv database hais txog hom ntawv cov ntaub ntawv khaws cia uas tuaj yeem tuav qhov sib txawv hom los yog ntau yam ntawm cov nqi. Thaum cov khoos phis tawj khaws cia cov ntaub ntawv nyob rau hauv variables, txhua qhov sib txawv yuav tsum tau xaiv ib qho txawv hom ntaub ntawv . Qee yam hom ntaub ntawv muaj raws li nram no: integers, cim, hlua, floating point tooj thiab arrays.

Yog li ntawd, dab tsi yog hom ntaub ntawv hauv SQL Server?

A hom ntaub ntawv yog tus cwj pwm uas qhia txog qhov hom ntawm cov ntaub ntawv cov khoom ntawd khaws tau. Nws tuaj yeem yog tus lej, cim kab, nyiaj txiag, hnub thiab sijhawm, thiab lwm yam. SQL Server muab ib daim ntawv teev npe hom ntaub ntawv uas txhais tag nrho hom ntawm cov ntaub ntawv uas koj siv tau xws li, txhais ib kem lossis tshaj tawm a sib txawv.

Hom ntaub ntawv twg yog nyiaj hli?

Cov ntaub ntawv zauv feem ntau yog siv los khaws cov ntaub ntawv xws li nqe, nyiaj hli thiab lwm yam. Tso cai rau koj khaws tus nqi 1, 0, lossis NULL. Cov khw tus lej tus nqi hauv qhov ntau ntawm 0 txog 255. Cov khw muag khoom tus lej tus nqi hauv thaj tsam ntawm -32, 768 txog 32, 767.

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