How to retrieve all child nodes from JSON file - snowflake-cloud-data-platform

Question

I have below JSON file, which is in the external stage, I'm trying to write a copy query into the table with the below query. But it's fetching a single record from the node "values" whereas I need to insert all child elements for the values node. I have loaded this file into a table with the variant datatype.
The query I'm using:
select record:batchId batchId, record:results[0].pageInfo.numberOfPages NoofPages, record:results[0].pageInfo.pageNumber pageNo,
record:results[0].pageInfo.pageSize PgSz, record:results[0].requestId requestId,record:results[0].showPopup showPopup,
record:results[0].values[0][0].columnId columnId,record:results[0].values[0][0].value val
from lease;
{
"batchId": "",
"results": [
{
"pageInfo": {
"numberOfPages": ,
"pageNumber": ,
"pageSize":
},
"requestId": "",
"showPopup": false,
"values": [
[
{
"columnId": ,
"value": ""
},
{
"columnId": ,
"value":
}
]
]
}
]
}

Answer 1

you need to use the LATERAL FLATTEN functions, something like this:
I created this table:
create table json_test (seq_no integer, json_text variant);
and then populated it with this JSON string:
insert into json_test(seq_no, json_text)
select 1, parse_json($${
"batchId": "a",
"results": [
{
"pageInfo": {
"numberOfPages": "1",
"pageNumber": "1",
"pageSize": "100000"
},
"requestId": "a",
"showPopup": false,
"values": [
[
{
"columnId": "4567",
"value": "2020-10-09T07:24:29.000Z"
},
{
"columnId": "4568",
"value": "2020-10-10T10:24:29.000Z"
}
]
]
}
]
}$$);
Then the following query:
select
json_text:batchId batchId
,json_text:results[0].pageInfo.numberOfPages numberOfPages
,json_text:results[0].pageInfo.pageNumber pageNumber
,json_text:results[0].pageInfo.pageSize pageSize
,json_text:results[0].requestId requestId
,json_text:results[0].showPopup showPopup
,f.value:columnId columnId
,f.value:value value
from json_test t
,lateral flatten(input => t.json_text:results[0]:values[0]) f;
gives these results - which I think is roughly what you are looking for:
BATCHID NUMBEROFPAGES PAGENUMBER PAGESIZE REQUESTID SHOWPOPUP COLUMNID VALUE
"a" "1" "1" "100000" "a" false "4567" "2020-10-09T07:24:29.000Z"
"a" "1" "1" "100000" "a" false "4568" "2020-10-10T10:24:29.000Z"