Video: DataFrame hauv spark Scala yog dab tsi?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
A Spark DataFrame yog ib qho kev faib tawm ntawm cov ntaub ntawv uas tau muab tso rau hauv cov kab npe uas muab kev ua haujlwm los lim, pab pawg, lossis suav cov sib sau ua ke, thiab tuaj yeem siv nrog Teeb SQL ntawv. DataFrames tuaj yeem tsim los ntawm cov ntaub ntawv tsim qauv, RDDs uas twb muaj lawm, cov ntxhuav hauv Hive, lossis cov ntaub ntawv sab nraud.
Ib yam li ntawd, koj tuaj yeem nug, DataFrame hauv Scala yog dab tsi?
Ib qho kev sib sau ua ke ntawm cov ntaub ntawv muab tso rau hauv kab npe. A DataFrame yog sib npaug rau lub rooj sib tham hauv Spark SQL. Xaiv ib kab los ntawm cov cov ntaub ntawv ncej , siv txoj kev siv hauv Scala thiab col hauv Java.
Dab tsi yog kev siv lub teeb hauv Scala? ( lit yog siv hauv Teeb los hloov tus nqi lus rau hauv kab tshiab.) Txij li thaum concat siv kab lus sib cav lit yuav tsum yog siv ntawm no.
Ib sab saum toj no, qhov txawv ntawm RDD thiab DataFrame hauv lub txim yog dab tsi?
Spark RDD APIs – Ib RDD stands rau Resilient Distributed Datasets. Nws yog Read-tsuas muab faib sau cov ntaub ntawv. RDD yog cov ntaub ntawv tseem ceeb ntawm Teeb . DataFrame hauv Spark tso cai rau cov neeg tsim khoom los tsim cov qauv mus rau ib qho kev faib tawm ntawm cov ntaub ntawv, tso cai rau qib siab abstraction.
Column hauv Spark ua dab tsi?
Spark nrog Kab () ua haujlwm yog siv los hloov npe, hloov tus nqi, hloov cov ntaub ntawv ntawm ib kab DataFrame uas twb muaj lawm thiab ua tau siv los tsim ib kab tshiab, ntawm no ncej, I yuav taug kev koj los ntawm feem ntau siv DataFrame kem ua haujlwm nrog Scala thiab Pyspark piv txwv.
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