It would be nice to take GENdbc and use it to generate SQL txt files that could be used for MySQL, Postgres and firebird. Actually, it would be better if we used DBF's and not the DBC just to insure 2.6 tables could be converted too. The case statement would not be very difficult:

Case "char"
replace C with VARCHAR
case "Number"
replace N with Number
case "date"
replace D with Date

Or something like that.

What I have done in the past is used gendbc and then a text editor to replace the "c(" with "VARCHAR(" etc.

I'm not to sure how upsize works - but it must do something like above too.
John