Parse JSON Array in T-SQL

Question

In our SQL Server table we have a json object stored with an array of strings. I want to programatically split that string into several columns. However, I cannot seem to get it to work or even if it's possible.

Is this a possibility to create multiple columns within the WITH clause or it is a smarter move to do it within the select statement?

I trimmed down some of the code to give a simplistic idea of what's given.

The example JSON is similar to { "arr": ["str1 - str2"] }

SELECT b.* FROM [table] a
OUTER APPLY
OPENJSON(a.value, '$.arr')
WITH
(
    strSplit1 VARCHAR(100) SPLIT('$.arr', '-',1),
    strSplit2 VARCHAR(100) SPLIT('$.arr', '-',2)
) b

Answer 1

Due to the tag [tsql] and the usage of OPENJSON I assume this is SQL-Server. But might be wrong... Please always specify your RDBMS (with version).

Your JSON is rather weird... I think you've overdone it while trying to simplify this for brevity...

Try this:

DECLARE @tbl TABLE(ID INT IDENTITY,YourJSON NVARCHAR(MAX));
INSERT INTO @tbl VALUES(N'{ "arr": ["str1 - str2"] }') --weird example...
                      ,(N'{ "arr": ["a","b","c"] }');  --array with three elements

SELECT t.ID
      ,B.[value] AS arr
FROM @tbl t
CROSS APPLY OPENJSON(YourJSON) 
WITH(arr NVARCHAR(MAX) AS JSON) A
CROSS APPLY OPENJSON(A.arr) B;

A rather short approach (but fitting to this simple example only) was this:

SELECT t.ID
      ,A.*
FROM @tbl t
OUTER APPLY OPENJSON(JSON_QUERY(YourJSON,'$.arr')) A 

Hint

JSON support was introduced with SQL-Server 2016

UPDATE: If the JSON's content is a weird CSV-string...

There's a trick to transform a CSV into a JSON-array. Try this

DECLARE @tbl TABLE(ID INT IDENTITY,YourJSON NVARCHAR(MAX));
INSERT INTO @tbl VALUES(N'{ "arr": ["str1 - str2"] }') --weird example...
                      ,(N'{ "arr": ["a","b","c"] }')  --array with three elements
                      ,(N'{ "arr": ["x-y-z"] }');     --array with three elements in a weird CSV format

SELECT t.ID
      ,B.[value] AS arr
      ,C.[value]
FROM @tbl t
CROSS APPLY OPENJSON(YourJSON) 
WITH(arr NVARCHAR(MAX) AS JSON) A
CROSS APPLY OPENJSON(A.arr) B
CROSS APPLY OPENJSON('["' + REPLACE(B.[value],'-','","') + '"]') C;

Some simple replacements in OPENJSON('["' + REPLACE(B.[value],'-','","') + '"]') will create a JSON array out of your CSV-string, which can be opened in OPENJSON.