Hi,
 
    I'm doing a project and I've have some problems.
    My table has (ID, atr1,..., atn), but there isn't any primary key because of the specifications, it's very similar to a Data warehouse, where every event is stored. It hasn't any delete, only inserts (more than 10^7) and many updates.
    The thing is that it takes too much time in execute. (In my case, before each update I've to do select to find which row I have to modify, and I suppose it does a table scan. To improve it, I've thought to use a Btree for ID column).
    I use JDBC. To make it works better, I use:
-  Prepared Statements,  
- setAutocommit(false), ( in my case I don't need transactions).  
- I'm been reading PostgreSQL mailing list archive to try to discover other kinds of "tune", or how to improve it.  
- I've also read FAQ and I've found "3.6) How do I tune the data base engine for better performance".   
    But in my case, would you think vacuum and analyze are good options? Can I do everything else? Can I  also disable the catalog? 
 
Thanks a lot
 
yours,
 
 
Cris..