tblMain
Event Num, Date, Additional Num
12, Jan1, 999
12, Jan1, 999
13, Sep4, <null>
14, Sep30, 82
14, Sep30, 82
15, Jun4, <null>
tblEvent
Event Num, Event Type, City1, City2, City3
12, Alpha, London, Beijing, New York
12, Beta, London, <null>, <null>
13, Gamma...