TIME datatype hauv SQL yog dab tsi?
TIME datatype hauv SQL yog dab tsi?

Video: TIME datatype hauv SQL yog dab tsi?

Video: TIME datatype hauv SQL yog dab tsi?
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Cov SQL ntawv Server TIME cov ntaub ntawv hom txhais a sij hawm ntawm ib hnub raws li 24-teev moos. Lub syntax ntawm lub TIME cov ntaub ntawv hom yog raws li nram no: 1. LUB SIJ HAWM [(fractional second scale)] Qhov fractional thib ob nplai qhia cov lej ntawm cov lej rau feem feem ntawm cov vib nas this.

Ib yam li ntawd, nws tau nug, dab tsi yog hom ntaub ntawv rau hnub thiab sijhawm hauv SQL?

SQL ntawv Server los nrog cov hauv qab no hom ntaub ntawv rau khaws cia a hnub los yog a hnub / sij hawm tus nqi hauv database: DATE - format YYYY-MM-DD. DATETIME - format: YYYY-MM-DD HH:MI:SS. SMALLDATETIME - format: YYYY-MM-DD HH:MI:SS.

Tsis tas li ntawd, lub sijhawm khaws cia hauv SQL li cas? Raws li SQL ntawv Cov ntaub ntawv neeg rau zaub mov, lub cav database khaws DATETIME tus nqi raws li ob tus lej. Thawj tus lej sawv cev rau hnub thiab tus lej thib ob yog tus sij hawm . 003 vib nas this tom qab ib tag hmo. Qhov ntawd txhais tau tias sij hawm 00:00:00.003 yog khaws cia ua 1,og sij hawm 00:00:01,000 yog khaws cia ua 300.

Hauv qhov no, hom ntaub ntawv twg yog lub sijhawm hauv Java?

TIME Hom . Cov hom ntaub ntawv sijhawm . Cov hom ntawv yog yyyy- MM -dd hh:mm:ss, nrog rau hnub tim thiab sij hawm qhov chaw khaws cia. Mapped rau java ua.

Lub sijhawm cov ntaub ntawv yog dab tsi?

Tiag tiag- cov ntaub ntawv sijhawm (RTD) yog cov ntaub ntawv xa tawm tam sim tom qab sau. Tiag- cov ntaub ntawv sijhawm feem ntau yog siv rau navigation lossis taug qab. Xws li cov ntaub ntawv feem ntau yog ua tiav siv tiag- sij hawm suav txawm tias nws tseem tuaj yeem khaws cia rau tom qab lossis off-line cov ntaub ntawv tsom xam. Tiag- cov ntaub ntawv sijhawm tsis zoo ib yam li dynamic cov ntaub ntawv.

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