BigQuery 中的 ROW 类型/构造函数

Question

Does BigQuery have the concept of a ROW , for example, similar to MySQL or Postgres or Oracle or Snowflake ? I know it sort of implicitly uses it when doing an INSERT... VALUES (...) , for example:

INSERT dataset.Inventory (product, quantity)
VALUES('top load washer', 10),
      ('front load washer', 20)

Each of the values would be implicitly be a ROW type of the Inventory table, but is this construction allowed elsewhere in BigQuery? Or is this a feature that doesn't exist in BQ?

Answer 1

I think below is a simplest / naïve example of such constructor in BigQuery

with t1 as (
  select 'top load washer' product, 10 quantity, 'a' type, 'x' category union all
  select 'front load washer', 20, 'b', 'y' 
), t2 as (
  select 1 id, 'a' code, 'x' value union all
  select 2, 'd', 'z'
)
select *
from t1
where (type, category) = (select as struct code, value from t2 where id = 1)   

Besides using in simple queries, it can also be use in BQ scripts - for example (another simplistic example)

declare type, category string;
create temp table t2 as (
  select 1 id, 'a' code, 'x' value union all
  select 2, 'd', 'z'
);    
set (type, category) = (select as struct code, value from t2 where id = 1);