阅读量:214
Hive支持复杂数据类型,如数组(ARRAY)、结构体(STRUCT)和Map
创建表时定义复杂数据类型:
CREATE TABLE example_table (
id INT,
name STRING,
address STRUCT<street:STRING, city:STRING, state:STRING, zip:STRING>,
hobbies ARRAY<STRING>,
contact_info MAP<STRING, STRING>
);
插入数据到包含复杂数据类型的表中:
INSERT INTO example_table (id, name, address, hobbies, contact_info)
VALUES (1, 'John Doe', STRUCT('123 Main St', 'New York', 'NY', '10001'), ARRAY('reading', 'traveling'), MAP('email', 'john.doe@example.com', 'phone', '123-456-7890'));
查询包含复杂数据类型的表:
SELECT * FROM example_table;
访问复杂数据类型中的单个元素:
SELECT id, name, address.street, address.city, address.state, address.zip, hobbies[0], contact_info['email'], contact_info['phone']
FROM example_table;
使用聚合函数处理复杂数据类型:
SELECT COUNT(DISTINCT hobbies) as unique_hobbies
FROM example_table;
使用JOIN操作将两个表连接在一起,其中一个表包含复杂数据类型:
CREATE TABLE table2 (
id INT,
age INT,
hobbies ARRAY<STRING>
);
INSERT INTO table2 (id, age, hobbies)
VALUES (2, 30, ARRAY('swimming', 'cycling'));
SELECT t1.id, t1.name, t1.address, t2.age, t2.hobbies
FROM example_table t1
JOIN table2 t2 ON t1.id = t2.id;
这些示例展示了如何在Hive中创建表、插入数据、查询数据以及处理复杂数据类型。您可以根据实际需求调整这些示例以满足您的用例。