Cov txheej txheem:
Video: Yuav ua li cas yog vim li cas rau tsim ib tug relational database?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Cov txiaj ntsig tseem ceeb ntawm cov kev sib txheeb database mus kom ze yog lub peev xwm tsim cov ntaub ntawv tseem ceeb los ntawm kev koom nrog cov rooj. Koom nrog cov rooj tso cai rau koj nkag siab txog kev sib raug zoo ntawm cov cov ntaub ntawv , los yog li cas cov rooj sib txuas. SQL suav nrog lub peev xwm suav, ntxiv, pab pawg, thiab tseem muab cov lus nug.
Yog li ntawd, lub hom phiaj ntawm kev sib raug zoo database yog dab tsi?
Relational databases siv rooj khaws cov ntaub ntawv. Cov qauv teb thiab cov ntaub ntawv teev tseg yog sawv cev raws li kab (thaj) thiab kab (cov ntaub ntawv) hauv ib lub rooj. Nrog rau cov ntaub ntawv sib raug zoo, koj tuaj yeem sib piv cov ntaub ntawv sai sai vim yog kev teeb tsa ntawm cov ntaub ntawv hauv kab.
Tsis tas li ntawd, vim li cas kev sib raug zoo database feem ntau nrov? Cov Relational database ua nrov vim SQL thiab nws cov programming abstraction. Nws yog qhov nyuaj rau kev tshem tawm kev sib txheeb databases los ntawm graph-based databases vim yog tsim los ntawm cov neeg siv hauv paus thiab kev teeb tsa. Relational databases tsuas yog yooj yim siv, qauv thiab tau tsim cov kev coj ua rau lawv cov kev tswj hwm.
Ib sab ntawm qhov no, koj yuav ua li cas tsim cov ntaub ntawv sib raug zoo?
Relational Database Design Process
- Kauj Ruam 1: Txhais Lub Hom Phiaj ntawm Database (Yuav tsum tau tsom xam)
- Kauj Ruam 2: Sau cov ntaub ntawv, teeb tsa hauv cov ntxhuav thiab qhia cov yuam sij tseem ceeb.
- Kauj Ruam 3: Tsim Kev Sib Raug Zoo ntawm Cov Rooj.
- Kauj Ruam 4: Ua kom zoo & normalize tus tsim.
Excel puas yog cov ntaub ntawv sib raug zoo?
Excel cov lub koom haum qauv qiv nws tus kheej zoo li cas databases ua haujlwm. Ib daim ntawv qhia, ib leeg, yog a database , tab sis tsis yog a kev sib raug zoo ib. Cov kev sib txheeb database yog ib qho kev sib txuas ntawm Master spreadsheet tables thiab tag nrho nws cov Slave tables los yog spreadsheets.
Pom zoo:
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Dab tsi yog qhov tsim qauv tsim qauv tsim thiab lub cev database tsim?
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