Cov txheej txheem:
Video: Dab tsi yog hom ntaub ntawv siv hauv Oracle?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Oracle muab cov ntaub ntawv hauv qab no built-in:
- tus cwj pwm hom ntaub ntawv . CHAR. NCHAR. VARCHAR2 thiab VARCHAR. NRHA 2. CLOB. NCLOB. LONG.
- NUMBER datatype.
- DATE datatype.
- binary hom ntaub ntawv . BLOB. BFILE. RAW. LONG RAW.
Cov lus nug tseem yog, pes tsawg hom ntaub ntawv nyob hauv Oracle?
BINARY_FLOAT yog 32-ntsis, ib leeg-precision floating-point naj npawb hom ntaub ntawv . Txhua BINARY_FLOAT tus nqi yuav tsum muaj 4 bytes.
Oracle Ua-hauv Hom ntaub ntawv.
| Hom | Kev piav qhia | Loj |
|---|---|---|
| LONG | Cov ntaub ntawv cim ntawm qhov ntev ntawm qhov sib txawv mus txog 2 gigabytes, siv rau kev sib tw rov qab. | 231 -1 bytes |
Tsis tas li ntawd, hom ntaub ntawv twg tau tshaj nrog tus lej? Cov ntaub ntawv hom thiab hom hom compatibility
| Hom ntaub ntawv | Tau tshaj hom hom |
|---|---|
| Binary | Number, Text, Duab |
| Char | Text, URL, E-mail, HTML Tag |
| Hnub tim | Hnub tim, hnub tim |
| Decimal | Tus lej |
Khaws qhov no hauv kev xav, dab tsi yog qhov ntev datatype hauv Oracle?
LONG yog ib Oracle cov ntaub ntawv hom khaws cia cim cov ntaub ntawv ntawm sib txawv ntev mus txog 2 Gigabytes ntev (qhov loj dua version ntawm VARCHAR2 hom ntaub ntawv ). Nco ntsoov tias ib lub rooj tsuas muaj ib qho xwb LONG kab.
Dab tsi yog hom ntaub ntawv hauv PL SQL?
PL/SQL muab ntau cov ntaub ntawv teev tseg ua ntej. Piv txwv li, koj tuaj yeem xaiv los ntawm integer, floating point, tus cwj pwm , BOOLEAN , hnub tim, sau, siv, thiab khoom loj (LOB) hom. PL/SQL kuj cia koj txhais koj tus kheej subtypes.
Pom zoo:
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