Video: Dab tsi yog qhov txawv ntawm SQL hnub thiab Util hnub?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Hnub tim yog ib daim ntawv nyias nyias nyob ib ncig ntawm millisecond tus nqi uas yog siv los ntawm JDBC los txheeb xyuas ib qho SQL DATE hom. Hnub tim tsuas yog sawv cev xwb DATE tsis muaj sij hawm cov ntaub ntawv thaum java. siv . Hnub tim sawv cev ob leeg Hnub tim thiab Time information.
Hauv qhov no, Java SQL hnub yog dab tsi?
Hnub tim chav kawm. Cov java ua . sql ua . Hnub tim piv txwv yog dav siv nyob rau hauv JDBC vim nws sawv cev rau hnub uas tuaj yeem khaws cia hauv database. Ib co constructors thiab txoj kev ntawm java ua.
Kuj Paub, puas yog SQL hnub tim khw lub sijhawm? sql ua . Hnub tim sawv cev a hnub , tsis a hnub thiab sij hawm . Hnub tim piv txwv yuav tsum yog 'normalized' los ntawm kev teeb tsa teev , feeb, vib nas this, thiab milliseconds rau xoom hauv qhov tshwj xeeb sij hawm cheeb tsam uas piv txwv yog txuam. Yog koj xav tau khw a hnub thiab sij hawm , koj yuav tsum nrhiav lwm hom - piv txwv li. java ua.
Ib sab saum toj no, Java Util hnub puas muaj sijhawm sijhawm?
A java ua . siv . Hnub ua tsis yog muaj a thaj tsam txuam nrog nws. Nws txoj kev toString() yuav ua rau nws tshwm sim muaj a thaj tsam , tab sis tsis yog.
Dab tsi yog qhov txawv ntawm Java thiab SQL?
Java yog ib hom lus-oriented programming lus tsim rau coding ntawm heev complex front-end thiab back-end daim ntaub ntawv. Java muaj zog tshaj PL/ SQL ntawv hauv kev ua lej ntau. Java zoo dua PL/ SQL ntawv ntawm txhua yam uas tsis koom nrog kev nkag mus rau hauv database, tshwj xeeb tshaj yog txoj cai.
Pom zoo:
Dab tsi yog qhov txawv ntawm qhov sib txawv hauv zos thiab thoob ntiaj teb hauv SQL Server?
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