Video: Dab tsi yog faib hauv SQL?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Cov SQL faib (/) tus neeg teb xov tooj siv rau faib ib qho kev nthuav qhia lossis tus lej los ntawm lwm tus. Piv txwv li: Kom tau txais cov ntaub ntawv ntawm 'cust_name', 'opening_amt', 'receive_amt', 'outstanding_amt' thiab ('receive_amt'*5/100) raws li kab lus 'commission' los ntawm cov neeg siv khoom nrog cov xwm txheej hauv qab no - 1. '
Kuj paub, koj faib ob tus lej hauv SQL li cas?
yog koj faib 2 tus nqi ntawm tus lej ces koj siv tus lej kev faib. Yog li kom tau cov lus teb koj xav tau ces koj siv FLOAT lossis DECIMAL / NUMERIC hom uas ua rau tsis muaj tus lej kev faib. yog li koj xav tau faib 2 tus lej los ntawm kev sib txawv los yog kab tus nqi koj yuav tsum tau CAST los yog hloov ib qho ntawm cov tus nqi mus rau FLOAT lossis DECIMAL.
Tom qab ntawd, lo lus nug yog, ua li cas koj nres qhov kev faib los ntawm xoom hauv SQL? Lwm txoj kev mus tiv thaiv kev faib los ntawm xoom yog siv NULLIF muaj nuj nqi. NULLIF xav tau ob qhov kev sib cav. Yog tias qhov kev sib cav sib npaug, NULLIF rov qab tus nqi null. Yog tias lawv tsis sib npaug, NULLIF rov qab thawj tus nqi.
Raws li, qhov kev ua haujlwm div yog dab tsi?
Cov DIV muaj nuj nqi yog siv rau integer division (x muab faib los ntawm y). Tus nqi integer raug xa rov qab.
Dab tsi yog division operator hauv DBMS?
SQL ntawv | DIVISION . Kev faib feem ntau yuav tsum tau thaum koj xav nrhiav cov koom haum uas cuam tshuam nrog txhua qhov chaw ntawm cov txheej txheem sib txawv. Cov kev faib ua haujlwm yog siv thaum peb yuav tsum ntsuas cov lus nug uas muaj lo lus tseem ceeb 'tag nrho'.
Pom zoo:
Dab tsi yog muab faib hauv Active Directory?
Txhua tus tswj hwm sau npe hauv ib lub hav zoov tswj hwm los ntawm Active Directory Domain Services suav nrog cov npe muab faib. Directory partitions tseem hu ua naming contexts. Ib phau ntawv muab faib yog ib feem sib txuas ntawm tag nrho cov npe uas muaj kev ywj pheej rov ua dua thiab teem caij cov ntaub ntawv
Code migration nyob rau hauv faib system yog dab tsi?
Kev lig kev cai, kev tsiv teb tsaws chaws hauv cov tshuab faib tau tshwm sim nyob rau hauv daim ntawv ntawm kev tsiv teb tsaws chaw nyob rau hauv uas tag nrho cov txheej txheem tau tsiv los ntawm ib lub tshuab mus rau lwm qhov. Lub tswv yim tseem ceeb yog tias tag nrho cov kev ua tau zoo tuaj yeem txhim kho yog tias cov txheej txheem raug hloov los ntawm hnyav-loaded mus rau lub teeb-loaded tshuab
Dab tsi yog qhov kev faib tawm hauv SQL?
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Dab tsi yog qhov tseem ceeb muab faib hauv Dynamo DB?
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Dab tsi yog kev hloov pauv hauv kev faib database system?
Ib qho kev faib tawm yog kev sib pauv hauv cov ntaub ntawv uas muaj ob lossis ntau lub network hosts koom nrog. Hauv kev xyaum ua lag luam feem ntau siv cov txheej txheem nruj nruj ob theem xauv (SS2PL) rau kev tswj hwm kev sib raug zoo, uas ua kom lub ntiaj teb serializability, yog tias tag nrho cov ntaub ntawv koom nrog siv nws