I'm at the stage now where I need to restructure my database as I've decided on a solution which will meet my requirement to avoid duplicate rows. 

      My issue is this - I have two core tables of 'organisations' and 'stations' as well as a table linking them to manage ownership relationships. Historically I have linked owners to the stations through a lookup on the 'station' table but this has left it impossible to sensibly manage joint owned stations. What I want to do is copy all the existing stations with the owners from the 'stations' table to the 'station ownership' linking table. The goal here is to retain the core station data, location and statistics in the station table but keep owners along with details where percentages owned are relevant in the 'station ownership' table. Other than the Row id there isn't anything unique about the station unless we include location information which I don't fully have, so can't use.

      My question (if I'm looking at this in the correct way) is how can I copy the data from table to table using the row id to  retain the relationship of the particular station.

Many Thanks

Simon