Video: Dab tsi yog pawg ntawm cov ntaub ntawv hauv lub rooj hash?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Ua pawg hauv a rooj rooj hais txog qib uas cov khoom zoo li "pw ua ke", thiab feem ntau cuam tshuam los ntawm ob qho tib si hash muaj nuj nqi siv thiab cov ntaub ntawv teeb raug tso. Koj xav kom tsis txhob muaj qib siab pawg , vim hais tias nyhav nce qhov tshwm sim ntawm hash kev sib tsoo thaum lub sijhawm.
Ib yam li ntawd, dab tsi yog clustering hauv hash table?
Thawj Ua pawg yog qhov nyiam rau txoj kev daws teeb meem kev sib tsoo xws li linear probing los tsim kev khiav ntev ntawm cov qhov qhib nyob ze ntawm hash txoj hauj lwm ntawm cov yuam sij.
Tsis tas li ntawd, yuav ua li cas thaum lub rooj hash puv? Hash rooj ua puv , thiab tej yam phem tshwm sim Wb hais tias nws yog ib qho array. Lawv ua haujlwm zoo li no: thaum lub rooj ua x% puv , koj tsim ib tug tshiab rooj rooj uas yog (hais) muab ob npaug rau qhov loj me, thiab txav tag nrho cov ntaub ntawv mus rau qhov tshiab rooj rooj los ntawm rehashing tag nrho cov khoom uas tau khaws cia rau hauv nws.
Ua raws li qhov no hauv kev pom, dab tsi yog linear probing hauv hash tables?
Linear kev soj ntsuam yog ib lub tswv yim hauv computer programming los daws kev sib tsoo hauv rooj rooj , cov ntaub ntawv cov qauv rau kev tswj xyuas ib qho kev sau ntawm tus yuam sij-tus nqi khub thiab nrhiav tus nqi cuam tshuam nrog tus yuam sij muab. Nrog rau quadratic kev soj ntsuam thiab ob npaug hashing , linear soj ntsuam yog ib daim ntawv qhib qhov chaw nyob.
Dab tsi yog hash pawg hauv Oracle nrog piv txwv?
A hash pawg muab lwm txoj hauv kev rau qhov tsis yog pawg rooj nrog ib qho index los yog ib qho index pawg . Nrog ib lub rooj indexed los yog index pawg , Oracle Database nrhiav cov kab hauv ib lub rooj siv cov txiaj ntsig tseem ceeb uas cov ntaub ntawv khaws cia hauv qhov ntsuas cais.
Pom zoo:
Dab tsi yog qhov sib txawv ntawm pab pawg cov ntaub ntawv thiab cov ntaub ntawv tsis yog pawg?
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