SQL: JSON 从嵌套对象中提取

Question

我有一个table这样的

id	对象
1	{"is_from_shopping_bag":true,"products":[{"price":{"amount":"18.00","currency":"USD","offset":100," amount_with_offset":"1800"},"product_id":"1234","数量":1}],"来源":"购物车"}
2	{"is_from_shopping_bag":false,"products":[{"price":{"amount":"80.00","currency":"USD","offset":100," amount_with_offset":"8000"},"product_id":"2345","数量":1}],"来源":"pdp"}

我正在 Hive 中执行 sql 查询以获取 'currency' 字段。

目前我可以运行

SELECT
    JSON_EXTRACT( obj, '$.products')
FROM my_table

哪个returns

对象
[{"price":{"amount":"18.00","currency":"USD","offset":100,"amount_with_offset":"1800"},"product_id":"1234","数量":1}]
[{"price":{"amount":"80.00","currency":"USD","offset":100,"amount_with_offset":"8000"},"product_id":"2345","数量":1}]

如何更深入地获取货币？

Answer 1

要获取第一个产品使用的货币：

SELECT
    id,JSON_EXTRACT( obj, '$.products[0].price.currency') first_product_currency
FROM my_table;

id	first_product_currency
1	"USD"
2	"USD"

要获取所有产品的货币，请使用：

SELECT
    id,JSON_EXTRACT( obj, '$.products[*].price.currency') multiple_currencies
FROM my_table;

id	multiple_currencies
1	["USD"]
2	["USD"]

SQL: JSON Extract from nested object