Theexplodefunction in Spark is used to split an array column into multiple rows, creating a new row for each element in the array. It takes an array column as input and returns a new DataFrame with each element of the array in a separate row. This function is especially useful when you ...
res0:Long=3Scala> sc.parallelize(List(2,3,4)).collect() res1:Array[Int] =Array(2,3,4)Scala> sc.parallelize(List(2,3,4)).first() res2:Int=2Scala> sc.parallelize(List(2,3,4)).take(2) res3:Array[Int] =Array(2,3) 新术语和重要单词以粗体显示。您在屏幕上看到的单词,例如菜单...
explode(expr) -Separates the elements of arrayexprinto multiple rows, or the elements of mapexprinto multiple rows and columns. Examples:> SELECT explode(array(10,20));1020explode_outer explode_outer(expr) -Separates the elements of arrayexprinto multiple rows, or the elements of mapexprinto ...
所以这里window()操作的本质是explode(),可由一条数据产生多条数据 然后对window()操作的结果,以window列和 word列为 key,做groupBy().count()操作 这个操作的聚合过程是增量的(借助 StateStore) 最后得到一个有window,word,count三列的状态集 4.2 OutputModes ...
# split() splits each line into an array, and explode() turns the array into multiple rows words = lines.select( explode(split(lines.value, ' ')).alias('word'), lines.timestamp ) # Group the data by window and word and compute the count of each group ...
class ConfigReader(ConfigReaderContract): def __init__(self, config_path): self.config_df = spark.read.option("multiLine", True).json(config_path) def read_source_columns_schema(self): exploded_df = self.config_df.select(explode(self.config_df["schema"].source_columns).alias("source_co...
*/object _01StructuredWordCountSQL{defmain(args:Array[String]):Unit={// TODO: step1. 构建SparkSession实例对象,相关配置进行设置val spark:SparkSession=SparkSession.builder().appName(this.getClass.getSimpleName.stripSuffix("$")).master("local[2]").config("spark.sql.shuffle.partitions","2")....
peopleDFhas 3 rows anddfhas 5 rows. Theexplode()method adds rows to a DataFrame. collect_list Thecollect_listmethod collapses a DataFrame into fewer rows and stores the collapsed data in anArrayTypecolumn. Let's create a DataFrame withletter1,letter2, andnumber1columns. ...
函数名: explode 包名: org.apache.spark.sql.catalyst.expressions.Explode 解释: explode(expr) - Separates the elements of arrayexprinto multiple rows, or the elements of mapexprinto multiple rows and columns. 将数组“expr”的元素分隔为多行,或将map“expr”的元素分隔为多行和多列。(类似于扁平化)...
array_join(array, delimiter[, nullReplacement])使用分隔符连接给定数组的元素，并可选地使用字符串替换...