Lub sijhawm Oracle Database yog dab tsi?

Video: Lub sijhawm Oracle Database yog dab tsi?

2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47

DB Sijhawm . DB Sijhawm yog a sij hawm qauv statistic uas yog cov sum ntawm Oracle txheej txheem CPU noj thiab tsis ua haujlwm tos sij hawm . Thaum optimizing Oracle systems peb feem ntau tsom rau txo " sij hawm ", txawm tias ntau zaus database kev ua haujlwm kuj yog ib feem ntawm qhov sib npaug.

Qhov sib thooj, lub sijhawm database yog dab tsi?

Lub sijhawm database yog tag nrho sij hawm siv los ntawm cov neeg siv cov txheej txheem xws li nquag ua haujlwm lossis nquag tos hauv a database hu.

Tsis tas li ntawd, lub sijhawm database hauv Oracle yog dab tsi? Sijhawm tsam yog teem caij thaum database tsim los yog siv CREATE DATABASE . Nws tuaj yeem hloov kho siv ALTER DATABASE lus txib. Database sij hawm tsis tuaj yeem hloov pauv yog tias ib kab ntawm hom TIMESTAMP Nrog [LOCAL] TIMEZONE muaj nyob rau hauv database . Sijhawm tsam tuaj yeem teeb tsa hauv Qhov Chaw cheeb tsam format or [+|-]HH:MM format.

Ntawm no, dab tsi yog datatype rau lub sijhawm hauv Oracle?

TIMESTAMP

Peb tuaj yeem nrhiav hnub thiab sijhawm tam sim no hauv Oracle li cas?

SELECT TO_CHAR(CURRENT_DATE, 'DD-MON-YYYY HH:MI:SS') Los ntawm dual; SELECT TO_CHAR(SYSDATE, 'DD-MON-YYYY HH:MI:SS') Los ntawm dual; Pom cov hnub tim thiab lub sij hawm system tam sim no nrog rau sij hawm cheeb tsam, siv CURRENT_DATE nkaus xwb.

Pom zoo:

Lub sijhawm database hauv Oracle yog dab tsi?

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