Video: Lus Qhuab Qhia hauv Symfony yog dab tsi?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Lus qhuab qhia yog lig decoupled los ntawm Symfony thiab siv nws yog xaiv tau. Tshooj no yog txhua yam hais txog lub Lus qhuab qhia ORM, uas lub hom phiaj cia koj daim ntawv qhia cov khoom rau cov ntaub ntawv sib raug zoo (xws li MySQL, PostgreSQL lossis Microsoft SQL). Koj tuaj yeem txuas ntxiv cov ntaub ntawv rau MongoDB siv Lus qhuab qhia ODM tsev qiv ntawv.
Ib yam li ntawd, koj tuaj yeem nug, ORM yog dab tsi hauv Symfony?
Nws yog ib phau ntawm cov cai uas qhia txog Lus Qhuab Qhia ORM raws nraim li cas cov tub ntxhais kawm ntawv thiab nws cov khoom yog mapped rau ib lub rooj database tshwj xeeb. Zoo, cov metadata no tuaj yeem teev nyob rau hauv ntau hom ntawv sib txawv, suav nrog YAML, XML lossis koj tuaj yeem nkag ncaj qha rau Cov Tub Kawm Ntawv hauv chav kawm siv cov lus piav qhia.
Ib yam li ntawd, cov lus qhuab qhia DBAL yog dab tsi? Cov Lus qhuab qhia Database Abstraction Layer ( DBAL ) yog txheej txheej abstraction uas zaum saum PDO thiab muaj qhov nkag siab zoo thiab hloov pauv API rau kev sib txuas lus nrog cov ntaub ntawv sib raug zoo tshaj plaws.
Cov lus qhuab qhia database yog dab tsi?
Cov Lus qhuab qhia Qhov project (los yog Lus qhuab qhia ) yog ib txheej ntawm PHP cov tsev qiv ntawv feem ntau tsom rau kev muab cov kev pabcuam persistence thiab muaj feem xyuam rau kev ua haujlwm. Nws cov khoom plig khoom plig yog cov khoom siv sib txuas lus (ORM) thiab cov database abstraction txheej nws yog ua rau saum.
ORM moj khaum yog dab tsi?
ORM tseem yog lwm nerd-acronym, nws luv luv rau Object Relational Mapping. Nyob rau hauv ib tug nutshell, ib ORM txoj haujlwm yog sau rau hauv ib hom lus taw qhia (xws li PHP, Java, C# thiab lwm yam …) thiab nws yog tsim los kom zoo qhwv ib ncig ntawm cov ntaub ntawv sib raug zoo.
Pom zoo:
Dab tsi yog zaj lus qhia nyob rau hauv Lus dab neeg ntawm Sleepy Hollow?
Sau: Washington Irving
Dab tsi yog lub ntsej muag qhia hauv kev sib txuas lus tsis hais lus?
Lub ntsej muag qhia yog ib lossis ntau qhov kev txav los yog txoj haujlwm ntawm cov leeg hauv qab ntawm daim tawv nqaij ntawm lub ntsej muag. Kev hais ntsej muag yog ib hom kev sib txuas lus tsis yog lus. Lawv yog ib qho tseem ceeb ntawm kev xa cov ntaub ntawv kev sib raug zoo ntawm tib neeg, tab sis lawv kuj tshwm sim nyob rau hauv feem ntau lwm hom tsiaj thiab lwm hom tsiaj
Dab tsi cuam tshuam cov lus qhia hauv kev sib txuas lus tsis yog lus?
Cov lus qhia cuam tshuam yog qhov hais lus thiab tsis hais lus ntawm kev cuam tshuam (kev xav). Cov kev qhia no tuaj yeem yog los ntawm lub ntsej muag, kev piav tes piav taw thiab lub cev lus, ntim thiab lub suab ntawm lub suab, luag, quaj, thiab lwm yam. Kev cuam tshuam cov duab tuaj yeem hloov kho lossis cuav yog li ib qho tuaj yeem tshwm sim, thaum lawv hnov lwm (piv txwv li luag ntxhi thaum tu siab)
Lub sij hawm nyob rau hauv ontology yog dab tsi yog hais txog cov lus piav qhia hierarchical thiab cov lus hais txog ib qho tshwj xeeb?
Lub schema yog ib lo lus ontology uas hais txog cov lus piav qhia hierarchical thiab cov lus hais txog ib lub npe. Ib lub npe sawv cev rau tag nrho lub tuam txhab lossis kev faib hauv ib lub tuam txhab. Ib tug cwj pwm yog ib tug yam ntxwv tshwj xeeb hais txog ib chav kawm, uas yog ib hom khoom
Dab tsi yog tus hais lus sau nws lub hom phiaj thiab dab tsi yog yam tseem ceeb uas yuav tsum nco ntsoov txog cov lus hais?
Cov neeg hais lus sau ntawv yog cov ntawv qhia uas tus neeg nthuav qhia siv thaum nthuav qhia qhov kev nthuav qhia. Lawv pab tus neeg nthuav qhia nco txog cov ntsiab lus tseem ceeb thaum muab kev nthuav qhia. Lawv tshwm sim ntawm tus swb thiab tuaj yeem pom tsuas yog los ntawm tus tshaj tawm thiab tsis yog cov neeg tuaj saib