SQL Server : display column with each data set

I'm exporting data out to a flat file to import into a SIEM. Is there a way to display as "column name = data" for each item?

SELECT 
    [Description], [MessageDescription], [CardNumber], 
    [TimeStamp_Server], [SPMDescription] [CardHolderID], 
    [FirstName], [MiddleName], [LastName],
    [CardStatusID], [CardStatusDescription], [Imprint],
    [TransactionNumber]
FROM 
    [DB].[dbo].[Message]
WHERE 
    CONVERT(varchar(10), TimeStamp_Server, 120) = CONVERT(varchar(10), GETDATE(), 120)

Here is how it currently presents in the flat file.

Description,MessageDescription,CardNumber,TimeStamp_Server,CardHolderID,FirstName,MiddleName,LastName,CardStatusID,CardStatusDescription,Imprint,TransactionNumber
North Entry,AccessGrantedNoEntry,0,2023-02-08 09:52:19,Retail Center C004 Converted PXL250-2DOOR,,,,,,,527312

I'd like it to display as this for each row

Description = North Entry,
MessageDescription = AccessGrantedNoEntry,
CardNumber = 0, 
TimeStamp_Server = 2023-02-08

... and so on.

This is a side issue (so community wiki), but you can significantly improve performance of this query by changing the WHERE clause like this (assuming TimeStamp_Server is a DateTime column):

WHERE TimeStamp_Server >= cast(cast(getdate() as date) as datetime) 
    AND TimeStamp_Server < cast(dateadd(day, 1, cast(getdate() as date)) as datetime)

This helps in three ways:

1. Thanks to cultural/internationalization issues, converting dates to and from string values is far slower and more error-prone than we'd like to believe. Sticking with Date functions and types will always perform better and be more accurate.
2. By shifting all the modifications to getdate(), so TimeStamp_Server is unaltered, we avoid needing to do the conversion on every row in the table.
3. By shifting all the modifications to getdate(), so TimeStamp_Server is unaltered, we preserve the use of any index that might exist for the column. This cuts to the core of database performance.

With a bit of JSON and string_agg()

Select B.NewVal
From ( 
       --Your Query Here-- 
     ) A
 Cross Apply (
                Select NewVal = string_agg(concat([key],' = ',value),',')
				 From openjson( (Select A.* For JSON Path,Without_Array_Wrapper  ) )
              ) B

A minimal reproducible example is not provided. So, I am shooting from the hip.

Please try the following conceptual example.

IMHO, the JSON or XML output format would be much more reliable.

SQL

-- DDL and sample data population, start
DECLARE @tbl TABLE (id INT PRIMARY KEY, case_date DATE, Product INT);
INSERT INTO @tbl (id, case_date, Product) VALUES
(55, '2022-08-01', 11),
(66, '2022-05-21', 51);
-- DDL and sample data population, end

SELECT t.*
	, result = STUFF(XMLData.query('
		for $x in /root/*
		return concat(", ", local-name($x), "=", $x/text()[1])
		').value('.', 'VARCHAR(4096)'), 1,2,'')
FROM @tbl AS t
CROSS APPLY (SELECT t.* FOR XML PATH(''), TYPE, ROOT('root')) AS t1(XMLData);

Output

Thank you @Stu for providing what I was seeking in a comment:

> So you want every column name reproduced on every row? That's going to significantly increase the size of the file! Just use
>
> select concat('columnName = ', ColumnName)Columename, ...
>