Extract data from Json string and divide into multiple columns

Question

I have a column in a table that has Jsonstring text:

[
    {
        "PType":{"code":"9","name":"Hospitality"},
        "PSubType":{"code":"901","name":"Hotel"},
        "AType":{"code":"9","name":"Hospitality"},
        "ASubType":{"code":"901","name":"Hotel"}
    }
]

How can I divide that into multiple columns using sql server query?

Answer 1

With SQL-Server 2016+ there is native JSON support:

DECLARE @json NVARCHAR(MAX)=
N'[
    {
        "PType":{"code":"9","name":"Hospitality"},
        "PSubType":{"code":"901","name":"Hotel"},
        "AType":{"code":"9","name":"Hospitality"},
        "ASubType":{"code":"901","name":"Hotel"}
    }
]';

SELECT A.[key]
      ,JSON_VALUE(A.value,'$.code') AS Code
      ,JSON_VALUE(A.value,'$.name') AS [Name]
FROM OPENJSON(JSON_QUERY(@json,'$[0]')) A;

The result

key         Code    Name
---------------------------------
PType       9       Hospitality
PSubType    901     Hotel
AType       9       Hospitality
ASubType    901     Hotel

Some explanation:

With JSON_QUERY() you can get the element within the array, OPENJSON will find all objects within and return them as derived table.

JSON_VALUE will read the internals into columns.

Hint

with a version below v2016 you should use another tool or think about a CLR function...

Answer 2

In SQL Server 2016+ you can use a combination of openjson (more info here) and cross apply:

declare @json nvarchar(max) = '[ { "PType":{"code":"9","name":"Hospitality"}, "PSubType":{"code":"901","name":"Hotel"}, "AType":{"code":"9","name":"Hospitality"}, "ASubType":{"code":"901","name":"Hotel"} } ]'

select
 [PT].[code] as Ptype_Code
,[PT].[name] as Ptype_Name
,[PS].[code] as PSubType_Code
,[PS].[name] as PSubType_Name
,[AT].[code] as AType_Code
,[AT].[name] as AType_Name
,[AS].[code] as ASubType_Code
,[AS].[name] as ASubType_Name

from   openjson (@json)
with
(
    PType  nvarchar(max) as json,
    PSubType  nvarchar(max) as json,
    AType  nvarchar(max) as json,
    ASubType  nvarchar(max) as json
) as lev1
cross apply openjson (lev1.PType)
with
(
    code int,
    name nvarchar(100)
) as PT
cross apply openjson (lev1.PSubType)
with
(
    code int,
    name nvarchar(100)
) as PS
cross apply openjson (lev1.AType)
with
(
    code int,
    name nvarchar(100)
) as [AT]
cross apply openjson (lev1.ASubType)
with
(
    code int,
    name nvarchar(100)
) as [AS]

Result: