Hello,

Finally I found out where I had a problem. I am writting this letter
for other people who will have to insert tons of records with one
transaction. Do not repeat my mistakes! :)

After inserts dont't do CommitRetaining or RollbackRetaining. Commit
or Rollback it as fast as possible.

Use LEFT JOIN very carefully :) Sometimes query with left join takes
ages to execute.

After unfinished transaction, when application was terminated (in my
case "never ending" select with left join) do sweep or backup and
restore. Sometimes sweep takes several hours to finish.

I think that firebird experts should write article about insering big
amount of records at one time. People like me could read it before
they repeat my mistakes. I believe that there is more things to avoid
doing many inserts with one transaction.