大查询 JSON 提取 Function

Question

I'm extracting 2 fields from a JSON using JSON_EXTRACT using BQ as the following:

select JSON_EXTRACT_SCALAR('Event_Value','$.user_id') as cid, JSON_EXTRACT_SCALAR('Event_Value','$.tsts') as ts

if the JSON format is missing one of the field I'm receiving NULLs all over the place.

Is there a way to overcome it?

Answer 1

I feel the fix is quite simple:

select JSON_EXTRACT_SCALAR(Event_Value,'$.user_id') as cid, JSON_EXTRACT_SCALAR(Event_Value,'$.tsts') as ts    

So, there are extra ' around Event_Value - thus Event_Value was treated not as a column name but rather as string