>Very good problem.
>Very good solution but struncture mean fields and indexes. What about any existing indexes?

Structure doesn't mean indexes. Indexes are extensions. I don't know how ppl use the tables with the same structure. They might or might not need indexes match. To me having same structures is usefull for appending from anoher and that doesn't need any indexes. If need be for indexes, it's easy to get them too :

Dimension arrIndexes[tagcount(),5]
For jx=1 to tagcount()
  arrIndexes[jx,1] = tag(jx) && Tagname
  arrIndexes[jx,2] = key(jx) && Index expr
  arrIndexes[jx,3] = iif(Primary(jx),'P',;
       iif(Candidate(jx),'C',;
       iif(unique(jx),'U','R'))) && Type
  arrIndexes[jx,4] = descending(jx) && Isdesecending
  arrIndexes[jx,5] = sys(2021,jx) && Filter expr
Endfor

Cetin