Cov txheej txheem:
Video: Koj ua li cas rau ntau qhov kev sib raug zoo hauv Salesforce?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Yuav kom tsim tau ob tus tswv-ntau yam kev sib raug zoo:
- Xyuas kom tseeb tias ob yam khoom koj xav kom cuam tshuam rau ib leeg twb muaj lawm.
- Ntawm qhov khoom sib txuas, tsim thawj tus tswv-ntau yam kev sib raug zoo teb.
- Ntawm qhov khoom sib txuas, tsim qhov thib ob tus tswv-ntau yam kev sib raug zoo .
Ntxiv rau qhov no, hom khoom twg pab txhawb ntau rau ntau txoj kev sib raug zoo hauv Salesforce?
Ib txoj kev sib tshuam khoom yog kev cai khoom nrog ob lub tswv yim nthuav dav kev sib raug zoo , thiab nws yog tus yuam sij rau kev ua ib qho ntau -rau- ntau kev sib raug zoo.
Ib yam li ntawd, ntau npaum li cas rau ntau txoj kev sib raug zoo hauv database nrog piv txwv? A ntau-rau-ntau txoj kev sib raug zoo tshwm sim thaum ntau cov ntaub ntawv nyob rau hauv ib lub rooj yog txuam nrog ntau cov ntaub ntawv nyob rau hauv lwm lub rooj. Rau piv txwv , a ntau-rau-ntau txoj kev sib raug zoo muaj nyob nruab nrab ntawm cov neeg siv khoom thiab cov khoom lag luam: cov neeg siv khoom tuaj yeem yuav ntau yam khoom, thiab cov khoom tuaj yeem yuav los ntawm ntau cov neeg siv khoom.
Tom qab ntawd, lo lus nug yog, ntau npaum li cas rau ntau txoj kev sib raug zoo zoo li?
A ntau-rau-ntau txoj kev sib raug zoo hais txog a kev sib raug zoo nruab nrab ntawm cov ntxhuav hauv cov ntaub ntawv thaum cov niam txiv kab hauv ib lub rooj muaj ntau tus menyuam kab hauv lub rooj thib ob, thiab rov ua dua. Cov ntau-rau-ntau txoj kev sib raug zoo feem ntau yog daim iav ntawm lub neej tiag tiag kev sib raug zoo nruab nrab ntawm cov khoom ob lub rooj sawv cev.
Muaj pes tsawg Lookup kev sib raug zoo nyob rau hauv Salesforce?
Txhua yam khoom raug tso cai kom muaj ib lossis ob tus tswv, lossis txog li 8 cov ntsiab lus. Koj tuaj yeem muaj tag nrho ntawm 40 Kev sib raug zoo teb nrog qhov siab kawg ntawm 2 Master Detail Kev Sib Raug Zoo. Yog li koj tuaj yeem muaj txhua yam 40 raws li Lookup Relationship fields, 38 Lookup and 2 MD 39 Nrhiav thiab 1 MD kev sib raug zoo teb ntawm ib yam khoom.
Pom zoo:
Vim li cas kev sib raug zoo algebra siv nyob rau hauv kev sib raug zoo database tswj?
RELATIONAL ALGEBRA yog ib hom lus nug uas siv dav heev. Nws sau cov xwm txheej ntawm kev sib raug zoo raws li kev tawm tswv yim thiab muab qhov tshwm sim ntawm kev sib raug zoo raws li cov zis. Nws siv ntau yam haujlwm los ua qhov haujlwm no. Relational algebra operations yog ua recursively ntawm kev sib raug zoo
Dab tsi yog qhov txawv ntawm kev sib raug zoo unary kev sib raug zoo binary thiab kev sib raug zoo ternary?
Kev sib raug zoo tsis sib xws yog thaum ob tus neeg koom hauv kev sib raug zoo yog tib lub koom haum. Piv txwv li: Cov ncauj lus yuav yog qhov yuav tsum tau ua ua ntej rau lwm yam kev kawm. Kev sib raug zoo ternary yog thaum peb lub koom haum koom nrog kev sib raug zoo
Dab tsi yog qhov txawv ntawm kev sib raug zoo thiab tsis muaj kev sib raug zoo databases?
Qhov sib txawv loj ntawm lawv yog li cas lawv tuav cov ntaub ntawv. Relational databases are structured.Non-relational databases are document-oriented. Qhov no hu ua cov ntaub ntawv hom cia tso cai ntau 'qeb' ntawm cov ntaub ntawv khaws cia hauv ib qho kev tsim lossis Cov Ntaub Ntawv
Dab tsi yog qee qhov tsis zoo ntawm lub sijhawm stamping txoj hauv kev rau kev tswj hwm kev sib raug zoo?
Qhov tsis zoo ntawm lub sij hawm stamping mus kom ze yog tias txhua tus nqi khaws cia hauv cov ntaub ntawv yuav tsum muaj ob lub sij hawm thwj ntxiv: ib qho rau lub sijhawm kawg ntawm daim teb tau nyeem thiab ib qho rau qhov hloov tshiab kawg. Lub sij hawm stamping yog li ua rau kom nco xav tau thiab cov ntaub ntawv ua haujlwm nyiaj siv ua haujlwm
Yuav ua li cas koj tsim ib tug rau ntau txoj kev sib raug zoo nyob rau hauv ib tug database system?
Txhawm rau tsim kom muaj kev sib raug zoo ib leeg rau ob qho tib si ntawm thaj chaw (feem ntau yog thawj qhov tseem ceeb thiab txawv teb chaws qhov tseem ceeb) yuav tsum muaj qhov ntsuas tshwj xeeb. Txhawm rau tsim kom muaj kev sib raug zoo ib-rau-ntau Lub teb ntawm ib sab (feem ntau yog qhov tseem ceeb) ntawm kev sib raug zoo yuav tsum muaj qhov ntsuas tshwj xeeb