Video: Ib qho piv txwv ntawm qhov khoom siv yog dab tsi?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Databases hauv Nkag mus muaj plaub yam khoom: rooj, queries, forms, thiab reports. Ua ke, cov khoom no tso cai rau koj nkag mus, khaws, txheeb xyuas, thiab sau koj cov ntaub ntawv raws li koj xav tau.
Hauv qhov no, cov khoom siv database yog dab tsi?
A database object yog tej yam txhais khoom hauv a database uas yog siv los khaws lossis siv cov ntaub ntawv. Qee qhov piv txwv ntawm database khoom suav nrog cov ntxhuav, views, pawg, ntu ntu, indexes, thiab cov lus sib piv. Lub rooj yog lub sijhawm no lub hom phiaj vim nws yog thawj thiab yooj yim tshaj plaws ntawm cov ntaub ntawv khaws cia hauv kev sib raug zoo database.
Tsis tas li ntawd, cov lus nug yog dab tsi? Query Object . A Query Object yog ib tug neeg txhais lus [Gang of Four], uas yog, tus qauv ntawm khoom uas tuaj yeem tsim nws tus kheej rau hauv SQL nug . Koj tuaj yeem tsim qhov no nug los ntawm kev xa-ntiv nplhaib rau cov chav kawm thiab cov teb es tsis yog cov ntxhuav thiab kab.
Tom qab ntawd, ib tus tuaj yeem nug, dab tsi yog qhov khoom nug hauv kev nkag?
Lus nug . Ib khoom uas muab kev cai saib cov ntaub ntawv los ntawm ib lossis ntau lub rooj. Lus nug yog ib txoj hauv kev tshawb nrhiav thiab sau cov ntaub ntawv los ntawm ib lossis ntau lub rooj. Thaum koj tsim ib nug hauv Nkag mus , koj tab tom txhais cov kev tshawb fawb tshwj xeeb kom pom cov ntaub ntawv koj xav tau.
Dab tsi yog qhov khoom tseem ceeb tshaj plaws hauv Access database?
rooj
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