在字符串列 bigquery 中查询 json

Posted 2023-03-24

【中文标题】在字符串列 bigquery 中查询 json

【英文标题】：query json in a string column bigquery

【发布时间】：2020-02-10 14:13:51

【问题描述】：

我想知道是否可以查询一个 json 字符串列，该列将取消嵌套产品而无需指定索引。

例子

with mytable as (
select 
'"ecommerce":"purchase":"actionField":"id":"T12345","affiliation":"Online Store","revenue":"35.43","tax":"4.90","shipping":"5.99","coupon":"SUMMER_SALE","products":["name":"Triblend android T-Shirt","id":"12345","price":"15.25","brand":"Google","category":"Apparel","variant":"Gray","quantity":1,"coupon":"","name":"Donut Friday Scented T-Shirt","id":"67890","price":"33.75","brand":"Google","category":"Apparel","variant":"Black","quantity":1]' as eec
)  
select 
JSON_EXTRACT_SCALAR(eec, "$['ecommerce'].purchase.actionField.id") AS order_id,
JSON_EXTRACT_SCALAR(eec, "$['ecommerce'].purchase.products[0].name") AS product_1
from mytable
union all
select
JSON_EXTRACT_SCALAR(eec, "$['ecommerce'].purchase.actionField.id") AS order_id,
JSON_EXTRACT_SCALAR(eec, "$['ecommerce'].purchase.products[1].name") AS product_1
from mytable

预期输出

order_id    product_1
T12345  Triblend Android T-Shirt
T12345  Donut Friday Scented T-Shirt

enter image description here

但我想获得这个输出而不必做产品[索引]的联合，但有一些东西会自动重复和取消嵌套产品内部的元素

【参考方案1】：

#standardSQL
CREATE TEMP FUNCTION json2array(input STRING)
RETURNS ARRAY<STRING>
LANGUAGE js AS """
  return JSON.parse(input).map(x=>JSON.stringify(x));
"""; 
WITH mytable AS (
  SELECT 
  '"ecommerce":"purchase":"actionField":"id":"T12345","affiliation":"Online Store","revenue":"35.43","tax":"4.90","shipping":"5.99","coupon":"SUMMER_SALE","products":["name":"Triblend Android T-Shirt","id":"12345","price":"15.25","brand":"Google","category":"Apparel","variant":"Gray","quantity":1,"coupon":"","name":"Donut Friday Scented T-Shirt","id":"67890","price":"33.75","brand":"Google","category":"Apparel","variant":"Black","quantity":1]' AS eec
)  
SELECT 
  JSON_EXTRACT_SCALAR(eec, "$['ecommerce'].purchase.actionField.id") AS order_id,
  JSON_EXTRACT_SCALAR(product, "$.name") AS product_1
FROM mytable,
UNNEST(json2array(JSON_EXTRACT(eec, "$['ecommerce'].purchase.products"))) product

有输出

Row order_id    product_1    
1   T12345      Triblend Android T-Shirt     
2   T12345      Donut Friday Scented T-Shirt