RE: Loosing files after backend crash

> The "relfilenode" attribute of the tuple contained the value 
> "326210". I tried to find the file with that name in the 
> database directory - it really was not there.

Did you look in lost+found?

> Thus, the backend crash has led not only to impossibility to 
> complete my task, but also to loosing some data. The sequence 
> was actually created in an already committed transaction, not 
> in the one, that crashed.

How much time passed after sequence creation till crash?
Did you use -F (fsync = NO)?

Vadim