Snowflake - Lateral flatten: Nested Objects - snowflake-cloud-data-platform

Question

This is a JSON nested object in one of the columns in snowflake table.
I wanted to pull the "id" which is part of statusCategory object.
Need help in deriving this.
"status":
{
"description": "",
"id": "10147",
"name": "Done",
"statusCategory":
{
"colorName": "green",
"id": 3,
"key": "done",
"name": "Done",
}
}
Tried the below snowflake query.
SELECT a1.value::varchar as Derivedstatus
,a2.value::varchar as Derivedid
FROM SnowflakeTable A
,lateral flatten(input => parse_json(FULL_PAYLOAD):fields:status:statusCategory) as a1
,lateral flatten(input => a1.value:"id") as a2
But does not give any output.

Answer 1

So for starters, the JSON you have is invalid, it needs one more layer of brackets:
{
"status":
{
"description": "",
"id": "10147",
"name": "Done",
"statusCategory":
{
"colorName": "green",
"id": 3,
"key": "done",
"name": "Done",
}
}
}
then how you use it, it seems to think there should be a fields: so that would require another layer:
{
"fields": {
"status":
{
"description": "",
"id": "10147",
"name": "Done",
"statusCategory":
{
"colorName": "green",
"id": 3,
"key": "done",
"name": "Done",
}
}
}
}
thus:
with SnowflakeTable(FULL_PAYLOAD) as (
select parse_json('{"fields":
{
"status":
{
"description": "",
"id": "10147",
"name": "Done",
"statusCategory":
{
"colorName": "green",
"id": 3,
"key": "done",
"name": "Done",
}
}}}')
)
SELECT
a.*
,FULL_PAYLOAD:fields
,FULL_PAYLOAD:fields:status
,FULL_PAYLOAD:fields:status:statusCategory
FROM SnowflakeTable A
gives:
{ "colorName": "green", "id": 3, "key": "done", "name": "Done" }
for the last part..
at which point your first flatten:
SELECT
a1.value::varchar as Derivedstatus
FROM SnowflakeTable A
,lateral flatten(input => FULL_PAYLOAD:fields:status:statusCategory) as a1
gives:
DERIVEDSTATUS
green
3
done
Done
what you are trying to do with the second layer of flatten is not clear.. as there are no more nested items to flatten..
So this part will need more explanation of what values you are hoping to exact.
Guess 1:
If you only have one status category, per status: you can just directly access the values:
SELECT
a.FULL_PAYLOAD:fields:status:statusCategory:key::text as key
,a.FULL_PAYLOAD:fields:status:statusCategory:id::text as Derivedid
,a.FULL_PAYLOAD:fields:status:statusCategory:name::text as DerivedStatus
FROM SnowflakeTable AS a
gives:
KEY
DERIVEDID
DERIVEDSTATUS
done
3
Done