Cov txheej txheem:
Video: Kuv yuav ua li cas thiaj li tau txais cov ntaub ntawv sau kawg hauv SQL Server?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Txiav txim siab Last Inserted Record hauv SQL Server
- SELECT @@IDENTITY. Nws xa rov qab tus nqi IDENTITY kawg uas tau tsim los ntawm kev sib txuas, tsis hais lub rooj uas tsim tus nqi thiab cov peev txheej ntawm nqe lus uas tsim tus nqi.
- SELECT SCOPE_IDENTITY()
- SELECT IDENT_CURRENT('TableName')
Ib yam li ntawd, tib neeg nug, Kuv yuav ua li cas thiaj nrhiav tau cov ntaub ntawv sau kawg hauv SQL Server?
Txiav txim siab Last Inserted Record hauv SQL Server
- SELECT @@IDENTITY. Nws xa rov qab tus nqi IDENTITY kawg uas tau tsim los ntawm kev sib txuas, tsis hais lub rooj uas tsim tus nqi thiab cov peev txheej ntawm nqe lus uas tsim tus nqi.
- SELECT SCOPE_IDENTITY()
- SELECT IDENT_CURRENT('TableName')
Tsis tas li ntawd, kuv yuav ua li cas thiaj li tau txais qhov kawg tso tus kheej kem tus nqi hauv SQL? IDENT_CURRENT() yuav muab rau koj tus nqi kawg muab tso rau rau hauv ib lub rooj tshwj xeeb los ntawm txhua qhov, los ntawm txhua tus neeg siv. @@ IDENTITY muab rau koj tus nqi kawg tsim los ntawm qhov tsis ntev los no INSERT nqe lus rau kev sib txuas tam sim no, tsis hais lub rooj lossis qhov twg.
Ib yam li ntawd, kuv yuav xaiv cov ntaub ntawv kawg hauv SQL li cas?
kom tau kawg row ib SQL ntawv -Database siv qhov no sql ua txoj hlua: Xaiv * Los ntawm TableName qhov twg id =( Xaiv max(id) NTAWM TableName); Cov zis: Kawg Kab ntawm koj db!
Yuav ua li cas koj thiaj nrhiav tau cov ntaub ntawv sau kawg hauv lub rooj hauv Oracle?
Yog tias koj tsis muaj hnub tim lossis lub sijhawm teev teev teev tseg hauv koj cov ntxhuav, khaws cov kab ntawv sau kawg hauv cov ntaub ntawv siv cov lus txib "ROWNUM"
- Qhib SQL*PLUS thiab nkag mus rau Oracle.
- Xaiv kab kawg tso rau hauv Oracle database siv "ROWNUM" hais kom ua. Piv txwv li, hom:
- Ntaus ";" los khiav cov lus nug SQL.
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