SQL Server 2012

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CREATE TABLE elbat
             (col1 integer,
              col2 datetime,
              col3 varchar(max),
              col4 varchar(4));
INSERT INTO elbat
            (col1,
             col2,
             col3,
             col4)
            VALUES (1,
                    getdate(),
                    'lorem',
                    'fail'),
                   (2,
                    getdate(),
                    'ipsum',
                    'warn'),
                   (6,
                    getdate(),
                    'dolor',
                    'ok');
3 rows affected

SELECT CASE col4
          WHEN 'fail' THEN
            'red'
          WHEN 'warn' THEN
            'yellow'
          ELSE
            'green'
        END 'tr/@class',
        (SELECT col1 'td',
               '',
               col2 'td',
               '',
               col3 'td',
               '',
               col4 'td'
               FOR XML PATH(''),
                       TYPE) 'tr'
        FROM elbat
        FOR XML PATH('table');


XML_F52E2B61-18A1-11d1-B105-00805F49916B


<table><tr class="red"><td>1</td><td>2019-01-23T13:05:31.573</td><td>lorem</td><td>fail</td></tr></table><table><tr class="yellow"><td>2</td><td>2019-01-23T13:05:31.573</td><td>ipsum</td><td>warn</td></tr></table><table><tr class="green"><td>6</td><td>2019-01-23T13:05:31.573</td><td>dolor</td><td>ok</td></tr></table>