>>>> 2011/05/04 16:57 +0200, Rocio Gomez Escribano >>>>
I suppose my solution is an Join, but they have no intersection
<<<<<<<<
Really?
Your examples are very much like a simple join, a special case of
... client OUTER JOIN user ON clientCodeDrivingLicense = userCodeDrivingLicense
What is wrong with that? (although actually MySQL does not do full outer joining. It is
needful to get that through a union of left join and right join, care taken that the
inner join in only one of them appear.)
Actually, your tables "client" and "user" look like the same table with field names
changed, no other difference. Field names have nothing to do with intersection.
