map_form_arrays(array<K>, array<V>): map<K, V>根据给定的键/值数组对创建一个映射;键中的元素不应为null SELECT map_from_arrays(array(1.0, 3.0), array('2', '4')); {"1.0":"2", "3.0":"4"} map_from_entries(array<struct<K, V>>): map<K, V>返回从给定数组创建的映射 SELECT ...
使用带用户密码clone的方式： git clone https://username:password@remote 当username和password中含有特殊...
map_filter map过滤 SELECT map_filter(map(1, 'a', 2, 'b'),(k,y)->(k>=1));{1:"a",2:"b"} map_from_arrays map转数组方式 SELECT map_from_arrays(array(1.0, 3.0), array('2', '4'));{1.0:"2",3.0:"4"} map_from_entries array转map SELECT map_from_entries(array((1, '...
以下是在其他列的基础上在Spark中添加map列的示例代码: 代码语言:txt 复制 from pyspark.sql import SparkSession from pyspark.sql.functions import col, lit, map_from_arrays # 创建SparkSession spark = SparkSession.builder.getOrCreate() # 创建示例DataFrame data = [("Alice", 25), ("Bob",...
Creates a new map column. The array in the first column is used for keys. The array in the second column is used for values. All elements in the array for key should not be null. C# [Microsoft.Spark.Since("2.4.0")]publicstaticMicrosoft.Spark.Sql.ColumnMapFromArrays(Microsoft.Spark.Sql...
show(truncate = false) // +---+---+---+ // |array(age, city) |map(name, age) |map_from_arrays(array(age, city), array(age, city))| // +---+---+---+ // |[25, New York] |
import java.util.Arrays; import java.util.Iterator; public class SparkFlatMapJava { public static void main(String[] args){ SparkConf conf = new SparkConf().setMaster("local").setAppName("SparkFlatMapJava"); JavaSparkContext sc = new JavaSparkContext(conf); ...
map: map_form_arrays / map_from_entries / map_concat array & map : element_at / cardinality 总结 spark sql 高阶函数可以避免用户维护大量的 udf ,且提高了性能,增强了复杂类型的处理能力。 collect_list / collect_set 返回的结构为 array ,可以直接使用高阶函数进行操作。
map_filter map_from_arrays map_from_entries map_keys map_values map_zip_with mask max max_by md5 mean median min min_by minute mode monotonically_increasing_id month months months_between named_struct nanvl negate negative next_day now nth_value ntile...
Since Spark 2.0.0,we internally use Kryo serializer when shuffling RDDs with simple types, arrays of simple types, or string type. 从Spark 2.0.0开始,我们在使用简单类型,简单类型数组或字符串类型对RDD进行混洗时,内部使用Kryo序列化程序。