Cov txheej txheem:
Video: Kuv yuav nug PostgreSQL database li cas?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
PostgreSQL SELECT nqe lus syntax
- Ua ntej, qhia cov kab lus ntawm lub rooj uas koj xav tau cov ntaub ntawv nug hauv SELECT clause. Yog koj retrieve cov ntaub ntawv los ntawm ntau kab, siv cov npe ntawm cov kab sib cais.
- Qhov thib ob, qhia lub npe ntawm lub rooj uas koj xav tau cov ntaub ntawv nug tom qab NTAWM lo lus tseem ceeb.
Xav txog qhov no, kuv yuav ua li cas txuas mus rau ib lub database tshwj xeeb hauv PostgreSQL?
Txuas rau PostgreSQL database server siv psql ua Ua ntej, tso tawm psql ua program thiab txuas mus rau PostgreSQL Database Server siv lub postgres neeg siv los ntawm nias lub psql ua icon raws li qhia hauv qab no: Thib ob, nkag mus rau cov ntaub ntawv tsim nyog xws li Server, Database , Chaw nres nkoj, Username, thiab Password. Nyem Enter kom lees txais lub neej ntawd.
Ib tug kuj yuav nug, Kuv yuav hloov pauv ntawm cov databases hauv PostgreSQL li cas? Ua ntej ya davhlau
- Kauj ruam 1: Nkag mus rau koj lub database. su - postgres.
- Kauj ruam 2: Nkag mus rau PostgreSQL ib puag ncig. psql ua.
- Kauj ruam 3: Sau koj PostgreSQL databases. Feem ntau, koj yuav tsum tau hloov ntawm cov ntaub ntawv mus rau database, tab sis ua ntej, peb yuav sau cov ntaub ntawv muaj nyob hauv PostgreSQL.
- Kauj ruam 4: Hloov ntawm Databases hauv PostgreSQL.
Hais txog qhov no, kuv yuav sau tag nrho cov databases hauv PostgreSQL li cas?
Koj yuav tsum txuas rau tus yog lawm database saib nws cov ntxhuav (thiab lwm yam khoom). Saib tus phau ntawv hais txog psql ua.
7 Teb
- npe lossis l: sau tag nrho cov databases.
- dt: sau tag nrho cov ntxhuav hauv cov ntaub ntawv tam sim no siv koj qhov search_path.
- dt * ib.: sau tag nrho cov ntxhuav hauv cov ntaub ntawv tam sim no tsis hais koj qhov search_path.
Koj nug ib lub rooj li cas?
Tsim ib lub rooj lus nug
- Ntawm Cov Tsim tab, hauv Cov Lus Nug Pab Pawg, nyem Query Design.
- Hauv Show Table dialog box, muab ob npaug rau-nias cov ntxhuav uas koj xav khaws cov ntaub ntawv.
- Hauv txhua lub rooj, ob-nias lub teb lossis cov teb uas koj xav siv hauv koj cov lus nug.
- Optionally, ntxiv tej kab lus rau kab Field.
Pom zoo:
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