在Spark中,我们通常使用DataFrame API来进行数据操作,下面是在Spark中使用collect_list的示例代码: frompyspark.sqlimportSparkSessionfrompyspark.sql.functionsimportcollect_list# 创建Spark会话spark=SparkSession.builder.appName("ArrayAggExample
9. override def getPartitions: Array[Partition] = firstParent[T].partitions 10. 11. override def compute(split: Partition, context: TaskContext) = 12. f(context, split.index, firstParent[T].iterator(split, context)) 13. } 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 这样R...
他们在函数列表中清楚地显示了array_agg（）：https://spark.apache.org/docs/latest/api/sql/index.h...
他们在函数列表中清楚地显示了array_agg（）：https://spark.apache.org/docs/latest/api/sql/index.h...
select course,count(distinct name) as student_count from ( select name ,explode(courses) as course from ( select name ,array_agg(courses) as courses from student group by name ) ) as temp group by course; coursestudent_count Science 3 Art 2 Math 3 English 2 History 1 需求5 直接在数...
name,array_sort(t1.courses) as courses from ( select name,array_agg(courses) as courses from students group by name ) as t1 t1的数据是: name courses Charlie ["Math","Art"] Bob ["English","History","Art"] Alice ["Math","Science"] Emma ["Math","English","Science"] David ["...
struct组合map array 结构 1.hive建表语句 droptableappopendetail;createtableifnotexistsappopendetail ( username String, appname String, opencountINT)rowformat delimited fields terminatedby'|'location'/hive/table/appopendetail';createtableifnotexistsappopentablestruct_map ...
Apache Spark是一个开源的分布式计算框架,用于处理大规模数据集的计算任务。在Spark中,agg是一个用于聚合操作的函数,用于对数据进行分组并进行聚合计算。 在给定的问答内容中,问题是关于...
array_position array_except array_union slice arrays_zip sort_array shuffle array_min array_max flatten sequence array_repeat array_remove array_distinct collection_funcs array_size size cardinality reverse concat map_funcs element_at lambda_funcs transform...
object WindowFunctionDemo{defmain(args:Array[String]):Unit={val spark=SparkSession.builder().appName("spark window function demo").master("local").getOrCreate()// 用于隐式转换,如Seq调用toDF,一些如max、min函数等。import spark.implicits._ ...