Reading JSON array containing JSON object into rows - sql

Question

Based from this answer I found one problem. JSON object is return as NULL.
Suppose that I have a JSON like this:
{
"array_in_json": [
{ "number": 1, "character": "A", "some_object": { "code": 65 } },
{ "number": 2, "character": "B", "some_object": { "code": 66 } },
{ "number": 3, "character": "C", "some_object": { "code": 67 } },
{ "number": 4, "character": "D", "some_object": { "code": 68 } }
]
}
With a query like this:
DECLARE #json NVARCHAR(MAX)
SET #json = '{
"array_in_json": [
{ "number": 1, "character": "A", "some_object": { "code": 65 } },
{ "number": 2, "character": "B", "some_object": { "code": 66 } },
{ "number": 3, "character": "C", "some_object": { "code": 67 } },
{ "number": 4, "character": "D", "some_object": { "code": 68 } }
]
}'
SELECT
a.[number],
a.[character],
a.[some_object]
FROM
OPENJSON(#json) WITH (
Actions NVARCHAR(MAX) '$.array_in_json' AS JSON
) AS i
CROSS APPLY (
SELECT * FROM
OPENJSON(i.Actions) WITH (
[number] NVARCHAR(MAX) '$.number',
[character] NVARCHAR(MAX) '$.character',
[some_object] NVARCHAR(MAX) '$.some_object'
)
) a
This's the result:
number | character | some_object
-------------------------------------------------
1 | 'A' | NULL
2 | 'B' | NULL
3 | 'C' | NULL
4 | 'D' | NULL
I want to know is there a way to get a result like this? (Return JSON as escaped string instead of NULL)
number | character | some_object
-------------------------------------------------
1 | 'A' | '{ "code": 65 }'
2 | 'B' | '{ "code": 66 }'
3 | 'C' | '{ "code": 67 }'
4 | 'D' | '{ "code": 68 }'

Answer 1

You need to use AS JSON option in your schema definition to specify that the $.some_object property contains an inner JSON object:
SELECT
a.[number],
a.[character],
a.[some_object]
FROM
OPENJSON(#json) WITH (
Actions NVARCHAR(MAX) '$.array_in_json' AS JSON
) AS i
CROSS APPLY (
SELECT * FROM
OPENJSON(i.Actions) WITH (
[number] NVARCHAR(MAX) '$.number',
[character] NVARCHAR(MAX) '$.character',
[some_object] NVARCHAR(MAX) '$.some_object' AS JSON
)
) a