#Register the DataFrame as a SQL temporary viewdf.CreateOrReplaceTempView("people") sqlDF = spark.sql("SELECT * FROM people") sqlDF.show()#+---+---+#| age| name|#+---+---+#+null|Jackson|#| 30| Martin|#| 19| Melvin|#+---|---| 您需要从某个表中选择所有列,例如people,并使...
对于第一个Map中的每个键，需要检查第二个Map中的值是否相同。钥匙也一样。
optionally rename somedf=df.select('name','age',F.col('dob').alias('date_of_birth'), )# Remove columnsdf=df.drop('mod_dt','mod_username')# Rename a columndf=df.withColumnRenamed('dob','date_of_birth')# Keep all the columns which also occur in another datasetdf=df.select(*(F...
In R’s dplyr package, Hadley Wickham defined the 5 basic verbs — select, filter, mutate, summarize, and arrange. Here are the equivalents of the 5 basic verbs for Spark dataframes. Select I can select a subset of columns. The methodselect()takes either a list of column names or an ...
‘格式’IINTEGERINTEGERI8BIGINTBIGINTSELECTCOLUMN_NAMEAS''字段名'',DATA _TYPEAS`数据类型`,CHARACTER_MAXIMUM_LENGTHAS`字符长度`,NUMERIC_PRECIS IONAS`数字长度`,NUMERIC_SCALEAS`小数位数`,IS_NULLABLEAS`是否允许非空`,CAS EWHENEXTRA=''auto_increment''THEN1ELSE0ENDAS`是否自增`,COLUM ...