Andy,

Thanks for the code.  In looking at this there are two things that come 
to mind:

1)  You probably should be running vacuum after the delete to clean up 
the table, but on a table this small, I doubt it will make any real 
difference.

2)  Why have you set autocommit on?  This should be much faster with 
autocommit off.

Actually I just did a quick test of the two changes I mentioned above. 
The first (vacuum) doesn't make any noticable difference, however 
turning autocommit off causes the timings on my machine to go from 14 
seconds to 6 seconds.  Better than 50% improvement.

thanks,
--Barry


andy wrote:
> To all those who responded ,
> Thanks for your response,
> 
> I have attached the test programs that I used in the form of text files. The
> contents should be self evident. Please have a look and comment.
> 
> I used j2sdk1.3.1 down load to linux machine from sun.com as my java platform
> and
> And  perl, v5.6.0 built for i386-linux.
>  The PostgreSQL driver for perl came from www.perl.org
>   The postgreSQL driver in jdbc7.0-1.2.jar
> 
> 
> Barry Lind wrote:
> 
> 
>>Andy,
>>
>>I would be interesting in knowing what version you did this test on,
>>what platform, and most importantly which JDK (and if the Sun JDK which
>>JVM: classic, hotspot client, hotspot server).
>>
>>thanks,
>>--Barry
>>
>>andy wrote:
>>
>>>Hi,
>>>
>>>I ran a few bench marks on JAVA writing to a postgreSQL table using  and
>>>found that for the same number of records added to the table as a
>>>similar PERL routine the following results :
>>>     PERL 39 seconds : JAVA 45 Seconds.
>>>In a similar experiment where PERL and JAVA did treir output to the
>>>screen and not to a table,
>>>
>>>JAVA took 3 seconds and PERL 310 Seconds.
>>>My conclusion is that the database driver to postgreSQL is still far
>>>from efficient in the JAVA implementation.
>>>
>>>Both tests were run on the same computer.
>>>
>>>I would appreciate your comments and suggestions.
>>>Andy Sewell
>>>
>>>
>>>---------------------------(end of broadcast)---------------------------
>>>TIP 5: Have you checked our extensive FAQ?
>>>
>>>http://www.postgresql.org/users-lounge/docs/faq.html
>>>
>>>
>>>
>>>
>>>------------------------------------------------------------------------
>>>
>>>/*
>>>   Java bench mark against perl count to 100 000 000
>>>*/
>>>import java.io.*;
>>>import java.util.*;
>>>
>>>public class lp{
>>>      
>>>      public lp() throws ClassNotFoundException, FileNotFoundException, IOException
>>>      {
>>>      int last = 1000;
>>>
>>>         GregorianCalendar day = new GregorianCalendar();
>>>      String time = day.getTime().toString();
>>>         int k=0;
>>>         for (int i=0; i<last ; i++) {
>>>             for (int p=0; p<last ; p++) {k=1+p;System.out.println(k);}
>>>          }      
>>>       
>>>       GregorianCalendar day1 = new GregorianCalendar();
>>>       String time2 = day1.getTime().toString();
>>>       System.out.println(time);
>>>       System.out.println(time2 + "\n" + k);
>>>              
>>>                        
>>>      }
>>>      
>>>public static void main(String[] args) {
>>>  try {
>>>        lp test = new lp();
>>>      } 
>>>       catch (Exception ex) {
>>>         System.err.println("Exception :" + ex);
>>>      ex.printStackTrace();
>>>      }
>>>}
>>>}
>>>
>>>
>>>
>>>------------------------------------------------------------------------
>>>
>>>/*
>>>   Java equivalent
>>>*/
>>>import java.io.*;
>>>import java.sql.*;
>>>import java.util.*;
>>>
>>>public class pg{
>>>      Connection conn;
>>>      Statement  stmt;
>>>      
>>>      public pg() throws ClassNotFoundException, FileNotFoundException, 
>IOException, SQLException
>>>      {
>>>         Class.forName("org.postgresql.Driver");
>>>      conn = DriverManager.getConnection("jdbc:postgresql:exkom", "andy", "");
>>>         conn.setAutoCommit(true);
>>>         stmt = conn.createStatement();
>>>      int last = 10000;
>>>      int res = stmt.executeUpdate("delete from junk");
>>>
>>>         GregorianCalendar day = new GregorianCalendar();
>>>      String time = day.getTime().toString();
>>>
>>>         for (int i=0; i<last ; i++) {
>>>          // try {
>>>                 res =  stmt.executeUpdate("insert into junk values(" + i + ")");
>>>              
>>>         //    } catch (SQLException e) {
>>>     //          System.out.println(e);
>>>     //        }
>>>          }      
>>>       
>>>       GregorianCalendar day1 = new GregorianCalendar();
>>>       String time2 = day1.getTime().toString();
>>>//     String time3 = day.getTime().toString();
>>>       System.out.println(time);
>>>       System.out.println(time2);
>>>//     System.out.println(time3);
>>>
>>>//     res.close();
>>>       stmt.close();
>>>       conn.close();
>>>              
>>>                        
>>>      }
>>>      
>>>public static void main(String[] args) {
>>>  try {
>>>        pg test = new pg();
>>>      } 
>>>       catch (Exception ex) {
>>>         System.err.println("Exception :" + ex);
>>>      ex.printStackTrace();
>>>      }
>>>}
>>>}
>>>
>>>/**
>>>
>>>
>>>$conn = Pg::connectdb("dbname=exkom");
>>>die $conn->errorMessage unless PGRES_CONNECTION_OK eq $conn->status;
>>>
>>># print "Enter a state code :";
>>># $state_code = <STDIN>;
>>>
>>># chomp $state_code;
>>>$result = $conn->exec("delete from junk");
>>>$end = 10000;
>>>
>>>$t0 = new Benchmark;
>>>
>>>for ($i=1; $i < $end; $i++) {
>>>     $result = $conn->exec("insert into junk values($i)");
>>>}
>>>
>>>$t1 = new Benchmark;
>>>$td = timediff($t1, $t0);
>>>print " the $end records took :", timestr($td) , "\n"
>>>**/
>>>
>>>
>>>------------------------------------------------------------------------
>>>
>>>
>>>---------------------------(end of broadcast)---------------------------
>>>TIP 3: if posting/reading through Usenet, please send an appropriate
>>>subscribe-nomail command to [EMAIL PROTECTED] so that your
>>>message can get through to the mailing list cleanly
>>>
>>> lp.java
>>>
>>> Content-Type:
>>>
>>> text/plain
>>> Content-Encoding:
>>>
>>> 7bit
>>>
>>>
>>> ------------------------------------------------------------------------
>>> lp.pl
>>>
>>> Content-Type:
>>>
>>> application/x-perl
>>> Content-Encoding:
>>>
>>> 7bit
>>>
>>>
>>> ------------------------------------------------------------------------
>>> pg.java
>>>
>>> Content-Type:
>>>
>>> text/plain
>>> Content-Encoding:
>>>
>>> 7bit
>>>
>>>
>>> ------------------------------------------------------------------------
>>> pg.pl
>>>
>>> Content-Type:
>>>
>>> application/x-perl
>>> Content-Encoding:
>>>
>>> 7bit
>>>
>>>
>>> ------------------------------------------------------------------------
>>> Part 1.6
>>>
>>> Content-Type:
>>>
>>> text/plain
>>> Content-Encoding:
>>>
>>> binary
>>>
>>>



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