SQL Server 2017

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CREATE TABLE [dbo].[LineItems] 
(
    [Id]        BIGINT IDENTITY (1, 1) NOT NULL,
    [Name]      NVARCHAR(255) NULL,
    [StartDate] DATETIME2(7) NULL,
    [EndDate]   DATETIME2(7) NULL,
    [Status]    TINYINT DEFAULT (CONVERT([tinyint], (0))) NOT NULL,
);
INSERT INTO [dbo].[LineItems]([Name],[StartDate],[EndDate],[Status]) 
VALUES('line item 1','2021-01-19T00:00:00','2021-01-22T00:00:00',0), 
      ('line item 2','2021-02-02T00:00:00','2021-02-03T00:00:00',1),
      ('line item 3','2021-02-21T00:00:00','2021-02-23T00:00:00',0)
3 rows affected

SELECT CONCAT(JSON_VALUE([value],'$.Id'),'.JSON') AS [file], [value]
  FROM OPENJSON(
                (SELECT TOP 3 * FROM [dbo].[LineItems] FOR JSON PATH)
                )


file
value


1.JSON
{"Id":1,"Name":"line item 1","StartDate":"2021-01-19T00:00:00","EndDate":"2021-01-22T00:00:00","Status":0}

2.JSON
{"Id":2,"Name":"line item 2","StartDate":"2021-02-02T00:00:00","EndDate":"2021-02-03T00:00:00","Status":1}

3.JSON
{"Id":3,"Name":"line item 3","StartDate":"2021-02-21T00:00:00","EndDate":"2021-02-23T00:00:00","Status":0}

file	value
1.JSON	{"Id":1,"Name":"line item 1","StartDate":"2021-01-19T00:00:00","EndDate":"2021-01-22T00:00:00","Status":0}
2.JSON	{"Id":2,"Name":"line item 2","StartDate":"2021-02-02T00:00:00","EndDate":"2021-02-03T00:00:00","Status":1}
3.JSON	{"Id":3,"Name":"line item 3","StartDate":"2021-02-21T00:00:00","EndDate":"2021-02-23T00:00:00","Status":0}