Get keys into JSON column in SQL Server 2017 - sql

Question

I have this Json in a column of type NVARCHAR(MAX) in SQL Server 2017:
{
"coreTimes": {
"TMP_CLINICAL_TIMES_ANESTHESIOLOGY_OUT_DATETIME": {
"value": 1
},
"TMP_CLINICAL_TIMES_ANESTHESIOLOGY_IN_DATETIME": {
"value": 2
},
"TMP_CLINICAL_TIMES_SURGICAL_OUT_DATETIME": {
"value": 3
},
"TMP_CLINICAL_TIMES_ROOM_IN_DATETIME": {
"value": 4
},
"TMP_CLINICAL_TIMES_ROOM_OUT_DATETIME": {
"value": null
},
"TMP_CLINICAL_TIMES_BLOCK_OUT_DATETIME": {
"value": null
},
"TMP_CLINICAL_TIMES_BLOCK_IN_DATETIME": {
"value": null
},
"TMP_CLINICAL_TIMES_SURGICAL_IN_DATETIME": {
"value": null
}
}
}
I need this result:
Column
{"value":1}
{"value":2}
{"value":3}
{"value":4}
{"value":null}
{"value":null}
{"value":null}
What SQL Server 2017 function can I use to get this result if json properties can change dynamically (the key 'coreTimes' is fixed)?
In Oracle I have used:
SELECT res.*
FROM sopinterventionsaux ,
JSON_TABLE ( operating_times, '$.coreTimes.*'
COLUMNS (
value VARCHAR2 ( 2000 ) FORMAT JSON PATH '$'
)
) res
In PostgreSQL:
select value from table, jsonb_each(column-> 'coreTimes')
And in SQL Server?

Answer 1

If I understand you correctly, you need to use OPENJSON() with default schema to parse the input JSON. In this case OPENJSON() returns a table with columns key, value and type:
Table:
DECLARE #json nvarchar(max) = N'{
"coreTimes": {
"TMP_CLINICAL_TIMES_ANESTHESIOLOGY_OUT_DATETIME": {
"value": 1
},
"TMP_CLINICAL_TIMES_ANESTHESIOLOGY_IN_DATETIME": {
"value": 2
},
"TMP_CLINICAL_TIMES_SURGICAL_OUT_DATETIME": {
"value": 3
},
"TMP_CLINICAL_TIMES_ROOM_IN_DATETIME": {
"value": 4
},
"TMP_CLINICAL_TIMES_ROOM_OUT_DATETIME": {
"value": null
},
"TMP_CLINICAL_TIMES_BLOCK_OUT_DATETIME": {
"value": null
},
"TMP_CLINICAL_TIMES_BLOCK_IN_DATETIME": {
"value": null
},
"TMP_CLINICAL_TIMES_SURGICAL_IN_DATETIME": {
"value": null
}
}
}'
CREATE TABLE Data (JsonData nvarchar(max))
INSERT INTO Data (JsonData) VALUES (#json)
Statement:
SELECT j.[value]
FROM Data d
CROSS APPLY OPENJSON(d.JsonData, '$.coreTimes') j
Result:
---------------
value
---------------
{"value": 1}
{"value": 2}
{"value": 3}
{"value": 4}
{"value": null}
{"value": null}
{"value": null}
{"value": null}
If you want to get the exact values for the value keys, you need to use OPENJSON() with explicit schema (with columns definitions) and additional APPLY operator.
Statement:
SELECT j2.[value]
FROM Data d
CROSS APPLY OPENJSON(d.JsonData, '$.coreTimes') j1
CROSS APPLY OPENJSON(j1.[value]) WITH ([value] int '$.value') j2
Result:
-----
value
-----
1
2
3
4
NULL
NULL
NULL
NULL

Answer 2

Please try following:
declare #j nvarchar(max) = '{
"coreTimes": {
"TMP_CLINICAL_TIMES_ANESTHESIOLOGY_OUT_DATETIME": {
"value": 1
},
"TMP_CLINICAL_TIMES_ANESTHESIOLOGY_IN_DATETIME": {
"value": 2
},
"TMP_CLINICAL_TIMES_SURGICAL_OUT_DATETIME": {
"value": 3
},
"TMP_CLINICAL_TIMES_ROOM_IN_DATETIME": {
"value": 4
},
"TMP_CLINICAL_TIMES_ROOM_OUT_DATETIME": {
"value": null
},
"TMP_CLINICAL_TIMES_BLOCK_OUT_DATETIME": {
"value": null
},
"TMP_CLINICAL_TIMES_BLOCK_IN_DATETIME": {
"value": null
},
"TMP_CLINICAL_TIMES_SURGICAL_IN_DATETIME": {
"value": null
}
}
}'
select L1.[Value] from OPENJSON (#j, '$.coreTimes') AS L1