Peb puas tuaj yeem khaws array hauv PostgreSQL?

Video: Peb puas tuaj yeem khaws array hauv PostgreSQL?

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

Muaj qee lub sijhawm koj tej zaum xav tau khw ntau tus nqi hauv ib database kem es tsis txhob hla ntau lub rooj. PostgreSQL muab koj no muaj peev xwm nrog cov array hom ntaub ntawv. Arrays yog qee cov ntaub ntawv tseem ceeb tshaj plaws rau khaws cia cov npe ntawm cov ntaub ntawv.

Ua li no, koj puas tuaj yeem khaws ib qho array hauv database?

Ib array yog qhov txawv txav tshwj xeeb uas tso cai khaws ib los yog ntau qhov tseem ceeb hauv ib qho kev sib txawv xws li. - tuav usernames lossis cov ntsiab lus hauv ib qho Array . Qee zaum, xav tau khaws Array rau MySQL database thiab muab nws. Hauv no nyeem, kuv qhia li cas koj tuaj yeem khaws ib qho Array hauv MySQL database thiab nyeem nws nrog PHP.

Kuj Paub, PostgreSQL khaws cov ntaub ntawv li cas? Thaum twg cov ntaub ntawv yog khaws cia hauv Postgres , Postgres nyob rau hauv lem khw uas cov ntaub ntawv nyob rau hauv cov ntaub ntawv ib txwm nyob rau hauv lub filesystem. Ua ke nrog qhov chaw ntawm qhov chaw ntawm lub cov ntaub ntawv directory, qhov no muab peb qhov chaw ntawm cov ntaub ntawv rau cov neeg lub rooj. Tag nrho cov ntaub ntawv yog khaws cia in /var/lib/ postgresql ua /9.5/main/base/16387/.

Yog li ntawd, qhov twg database tuaj yeem tuav tsis tau?

Nco tseg: MySQL thiab Java DB tam sim no ua tsis yog txhawb nqa ARRAY SQL cov ntaub ntawv hom.

Unnest yog dab tsi hauv Postgres?

PostgreSQL UNNEST () muaj nuj nqi Cov haujlwm no yog siv los nthuav cov array mus rau ib pawg kab. Syntax: tsis sib haum (anyarray) Rov qab Hom: setof anyelement.

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