What (the hell) is SQL Exception called Function sequence error?

Question

...doing in a code like this:
ResultSet friends=...executeQuery...
while (friends.next())
log.append(friends.getString("sendergsm"));
somewhere in between that loop, or sometimes the loop runs out fine, and sometimes it throws SQLException called General Error. Not guite normal...

Answer 1

Thank you for replying... that must be agains some of the policies of the sun, to make methods that may be called normally, but may cause an error.
Anyway, this is my first database application. The number of problems I've had in few days is unbelivable. I wonder does it load the drivers from disk or something everytime it reads one record from database. I mean when I did the above query, the table had about 10 entries (the program showed 5 to 10 before function sequense error) and displaying each record to TextArea took over second. (In paradox (The dosversion) this would have taken less than a second).
And paradox tables doesn't work at all because it raises exception: Table isn't expected format. If I set paradox 4.0 drivers and put paradox 4.0 tables, you would guess that the format would be expected. And you cannot create paradox tables with SQL. Now I need to use access databases. How can database containing 60 records be 500kb:s? When it will contain 50000 new records every day, i guess I'll be in problem. Each tranaction (say 5 simple queries) taking minutes... heelp meee!!