MS SQL Json array processing with separate arrays - json

Question

I have a problem with JSON data and how to get it in SQL table so the data is:
[
{
"id":"1121131",
"idGroups":[
"123",
"X999"
],
"idGroupNames":[
"Neutral",
"Service"
]
},
{
"id":"2233154",
"idGroups":[
"654321"
],
"idGroupNames":[
"Position"
]
}
]
and the desired output is
Id
idGroups
idGroupNames
1121131
123
Neutral
1121131
X999
Service
2233154
654321
Position
I have trying to get the desired result with OPENJSON() and CROSS APPLY, but I think that I'm not getting anywhere.
my original attempt was
DECLARE #json NVARCHAR(MAX) = N'[
{
"id":"1121131",
"idGroups":[
"123",
"X999"
],
"idGroupNames":[
"Neutral",
"Service"
]
},
{
"id":"2233154",
"idGroups":[
"654321"
],
"idGroupNames":[
"Position"
]
}
]'
SELECT id,idGroup,idGroupName FROM OPENJSON (#json)
WITH (
id INT 'strict $.id',
idGroups NVARCHAR(MAX) '$.idGroups' AS JSON,
idGroupNames NVARCHAR(MAX) '$.idGroupNames' AS JSON
) CROSS APPLY OPENJSON(idGroups)
WITH (
idGroup VARCHAR(500) '$'
) CROSS APPLY OPENJSON(idGroupNames)
WITH (
idGroupName VARCHAR(500) '$'
)

Answer 1

You need to use OPENJSON() with default schema and two additional APPLY operators. The following statement is a possible solution to your problem:
JSON:
DECLARE #json nvarchar(max) = N'[
{
"id":"1121131",
"idGroups":[
"123",
"X999"
],
"idGroupNames":[
"Neutral",
"Service"
]
},
{
"id":"2233154",
"idGroups":[
"654321"
],
"idGroupNames":[
"Position"
]
}
]'
Statement:
SELECT j.id, j1.[value] AS idGroups, j2.[value] AS idGroupNames
FROM OPENJSON(#json) WITH (
id nvarchar(7) '$.id',
idGroups nvarchar(max) '$.idGroups' AS JSON,
idGroupNames nvarchar(max) '$.idGroupNames' AS JSON
) j
CROSS APPLY OPENJSON(j.idGroups) j1
CROSS APPLY OPENJSON(j.idGroupNames) j2
WHERE j1.[key] = j2.[key]

Answer 2

You can do it without a third OPENJSON, using JSON_VALUE and a dynamic path.
This only works in SQL Server 2017+
DECLARE #json nvarchar(max) = N'[
{
"id":"1121131",
"idGroups":[
"123",
"X999"
],
"idGroupNames":[
"Neutral",
"Service"
]
},
{
"id":"2233154",
"idGroups":[
"654321"
],
"idGroupNames":[
"Position"
]
}
]';
SELECT j.id, j1.[value] AS idGroups, JSON_VALUE(j.idGroupNames, '$[' + j1.[key] + ']') AS idGroupNames
FROM OPENJSON(#json) WITH (
id nvarchar(7) '$.id',
idGroups nvarchar(max) '$.idGroups' AS JSON,
idGroupNames nvarchar(max) '$.idGroupNames' AS JSON
) j
CROSS APPLY OPENJSON(j.idGroups) j1;
db<>fiddle