Ama-Database Consistency States Awukuthi Kudingeka Idatha Yodwa Ye-Database
I-Database Consistency ithi idatha kuphela evumelekile izobhalwa ku-database. Uma ukuthengiswa kwenziwa okwephula imithetho yokuvumelana kwemininingwane yedatha, konke ukuthengiswa kuzolungiswa futhi i-database izobuyiselwa esimweni sayo sokuqala. Ngakolunye uhlangothi, uma ukuthengiselana kwenziwa ngokuphumelelayo, kuzothatha idatha kusuka kumbuso owodwa ohambisana nemithetho kwenye indawo ehambisana nemithetho.
Ukuvumelana kokugcina idatha akusho ukuthi ukuthengiselana kulungile, kuphela ukuthi ukuthengiselana akuzange kwephule imithetho echazwe nguhlelo. Ukuzihlanganisa kwedatha kubalulekile ngoba ilawula idatha ezayo futhi inqaba idatha engafanele emithethweni.
Isibonelo soMthetho Wokubambisana Emsebenzini
Isibonelo, ikholomu ku-database ingaba namanani e-coin flip kuphela njenge "amakhanda" noma "imisila." Uma umsebenzisi uzama ukufaka "emaceleni," imithetho ehambisanayo yedatha ngeke ivumele.
Ungase ube nolwazi ngemithetho ehambisanayo ngokushiya insimu kwifomu lewebhu lewebhu. Uma umuntu egcwalisa ifomu ku-intanethi bese ekhohlwa ukugcwalisa esinye sezikhala ezidingekayo, inani le-NULL liya egciniwelwazi, okwenza ifomu lilahlwe kuze kufike isikhala esingenalutho kuso.
Ukubambisana yisigaba sesibili se- ACID model (Atomicity, Consistency, Isolation, Ukuhlala), okuyinto isethi yemihlahlandlela yokuqinisekisa ukunemba kokuthengiselana kwedatha.