JSON comparison function in Bigquery

Question

Is there any way to have a valid JSON object comparison function in BigQuery. Here are a few examples of input/output I'd like to see:

# all should result in TRUE
SELECT JSON '1' < JSON '2'
SELECT JSON '9' < JSON '10'
SELECT JSON '"a"' < '"b"'
SELECT JSON '"D"' < JSON '"a"'
SELECT JSON 'false' < JSON 'true'

Perhaps it would need a JS udf or something as it involves type-interpolation...perhaps recursively, but seeing what might be possible here.

Answer 1

The example provided does not show any nested structure. Therefore, the solution will not include any recursion. The JSON have to be interpreted in different formats: numbers and strings. This cannot be done in SQL and a JavaScript UDF is needed.

create temp function json_is_smaller(a json, b json)
returns bool
language js as
"""
return a<b
""";
with tbl as (SELECT JSON '1' a , JSON '2' b
UNION ALL SELECT JSON '9' , JSON '10'
UNION ALL SELECT JSON '"a"' , JSON '"b"'
UNION ALL SELECT JSON '"D"' , JSON '"a"'
UNION ALL SELECT JSON 'false' , JSON 'true')

select *,  json_is_smaller(a,b)
from tbl