load JSON into table with GUID primary key

from_json.sql

DECLARE @json NVARCHAR(MAX) = N'{"json":"here"}';
INSERT INTO tableName (Id, columnA, columnB, ...)
SELECT NEWID(), * FROM OPENJSON(@json)
WITH (
    columnA     VARCHAR(255)     '$.columnA',
    columnB     VARCHAR(255)     '$.columnB',
    ...
)