Cov txheej txheem:
Video: Qhov kev zam SQL yog dab tsi?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Ib kev zam uas muab cov ntaub ntawv ntawm kev nkag mus rau database yuam kev los yog lwm yam yuam kev. Txhua SQLException muab ntau yam ntaub ntawv: ib txoj hlua piav txog qhov yuam kev . ib txoj hlua "SQLstate", uas ua raws li XOPEN SQLstate cov lus cog tseg lossis cov SQL ntawv : 2003 conventions.
Raws li txoj cai, vim li cas SQL kev zam tshwm sim?
A SQL kev zam ua tau tshwm sim nyob rau hauv tus tsav tsheb los yog los ntawm lub database. Piv txwv li, ib tug syntax yuam kev hauv SQL ntawv nqe lus yuav ua rau a SQL kev zam . Lossis peb tsis muaj kev tso cai los hloov lub rooj. Thaum zoo li no kev zam tshwm sim , ib yam khoom ntawm hom SQLException yuav raug xa mus rau lub catch clause.
Qhov thib ob, qhov kev zam JDBC yog dab tsi?
- Java.sql. BatchUpdateException.
- java.sql. SQLException.
- java.sql. DataTruncation.
- java.sql. SQLWarning.
Ib yam li ntawd, koj ua li cas rau kev zam hauv SQL?
Yuav ua li cas daws SQL Exceptions
- Rov qab tswj xyuas tus txheej txheem niam txiv uas hu ua subprocedure uas tsa qhov kev zam.
- Siv ib lub sij hawm thaum twg los txiav txim rau ib qho kev zam-tswj niaj hnub los yog ua lwm yam.
- Kov qhov kev zam ntawm qhov chaw nrog cov lus sib xyaw SQL.
Dab tsi yog tus neeg siv txhais kev zam piav nrog piv txwv?
Cov neeg siv - txhais Kev cai Kev zam hauv Java. Java muab peb qhov chaw los tsim peb tus kheej kev zam uas yog qhov pib muab tau cov chav kawm ntawm Kev zam . Rau piv txwv MyException hauv qab no code txuas ntxiv rau Kev zam chav kawm. Tus tsim ntawm Kev zam chav kawm kuj tuaj yeem raug hu tsis muaj parameter thiab hu rau super tsis tas yuav tsum tau ua.
Pom zoo:
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