Re: really quick multiple inserts can use COPY?
От | nicky |
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Тема | Re: really quick multiple inserts can use COPY? |
Дата | |
Msg-id | 457E6472.9010707@valuecare.nl обсуждение исходный текст |
Ответ на | Re: really quick multiple inserts can use COPY? ("Jens Schipkowski" <jens.schipkowski@apus.co.at>) |
Список | pgsql-performance |
Jens Schipkowski wrote: > Thanks a lot to all for your tips. > > Of course, I am doing all the INSERTs using a transaction. So the cost > per INSERT dropped from 30 ms to 3 ms. > The improvement factor matches with the hint by Brian Hurt. > Sorry, I forgot to mention we are using PostgreSQL 8.1.4. > Thanks for the code snippet posted by mallah. It looks like you are > using prepared statements, which are not available to us. > But I will check our database access if its possible to do a > workaround, because this looks clean and quick to me. > > regards > Jens Schipkowski > > > On Mon, 11 Dec 2006 17:53:52 +0100, Guillaume Cottenceau <gc@mnc.ch> > wrote: > >> "Jens Schipkowski" <jens.schipkowski 'at' apus.co.at> writes: >> >>> Hello! >>> >>> In our JAVA application we do multiple inserts to a table by data from >>> a Hash Map. Due to poor database access implemention - done by >>> another company (we got the job to enhance the software) - we cannot >>> use prepared statements. (We are not allowed to change code at >>> database access!) >>> First, we tried to fire one INSERT statement per record to insert. >>> This costs 3 ms per row which is to slow because normally we insert >>> 10.000 records which results in 30.000 ms just for inserts. >>> >>> for(){ >>> sql = "INSERT INTO tblfoo(foo,bar) >>> VALUES("+it.next()+","+CONST.BAR+");"; >>> } >> >> You should try to wrap that into a single transaction. PostgreSQL >> waits for I/O write completion for each INSERT as it's >> implicitely in its own transaction. Maybe the added performance >> would be satisfactory for you. >> > > > > --** > APUS Software GmbH > > ---------------------------(end of broadcast)--------------------------- > TIP 7: You can help support the PostgreSQL project by donating at > > http://www.postgresql.org/about/donate > > > This link might be what you are looking for, it has some information about implementing COPY in the JDBC driver. Check the reply message as well. http://archives.postgresql.org/pgsql-jdbc/2005-04/msg00134.php Another solution might be to have Java dump the contents of the HashMap to a CVS file and have it load through psql with COPY commands. Good luck, Nick
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