SQL Server 2017 (Linux)

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CREATE TABLE dbo.Person(RecordNumber int, FirstName nvarchar(255));

INSERT dbo.Person(RecordNumber, FirstName) VALUES
(167196, N'Mark');

CREATE TABLE dbo.SessionLive(SessionCode char(5), SessionAtLocationID int);

INSERT dbo.SessionLive(SessionCode, SessionAtLocationID) VALUES
('T4182', 8105),
('T4183', 8106),
('T4190', 8113),
('T4179', 8102);

CREATE TABLE dbo.XPersonSchedule(PersonID int, SessionAtLocationID int);

INSERT dbo.XPersonSchedule(PersonID, SessionAtLocationID) VALUES
(167196,      8105),
(167196,      8106),
(167196,      8113),
(167196,      8102);
9 rows affected

/* and maybe some sample desired results

PersonID    FirstName    SessionCode
----------- ----------- -----------
167196      Mark         T4182<crlf>T4183<crlf>T4190<crlf>T4179
*/
    SELECT PersonID = p.RecordNumber, p.FirstName, 
      SessionCodes = STUFF((
        SELECT CONCAT(char(13),char(10),sl.SessionCode)
          FROM dbo.SessionLive AS sl
          INNER JOIN dbo.XPersonSchedule AS xps
            ON sl.SessionAtLocationID = xps.SessionAtLocationID
          WHERE xps.PersonID = p.RecordNumber
          FOR XML PATH(''), TYPE
        ).value(N'./text()[1]', N'varchar(max)'), 1, 2, '')
    FROM dbo.Person AS p
    GROUP BY p.RecordNumber, p.FirstName;


PersonID
FirstName
SessionCodes


167196
Mark
T4182
T4183
T4190
T4179


    SELECT PersonID = p.RecordNumber, p.FirstName,
      SessionCodes = STRING_AGG(sl.SessionCode, char(13)+char(10))
    FROM dbo.SessionLive AS sl
    INNER JOIN dbo.XPersonSchedule AS xps
      ON sl.SessionAtLocationID = xps.SessionAtLocationID
    INNER JOIN dbo.Person AS p
      ON xps.PersonID = p.RecordNumber
    GROUP BY p.RecordNumber, p.FirstName;


PersonID
FirstName
SessionCodes


167196
Mark
T4182
T4183
T4190
T4179