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Re: Getting results from oracle query suck!

From: mike <mike.scheuterX_at_alltel.com>
Date: Wed, 5 May 1999 07:58:02 -0500
Message-ID: <7gpfbs$rho8@amber.alltel.com> 





The server machine has lots of RAM and plenty of processor.  The NT
performance monitor shows CPU usage around 2% and lots of memory available
(re no swapping).  There is no other activity on this server box, no logins,
shared drives, nothing.  The data store on this server has 6 drives arranged
as raid 5 through hardware.



The java code is simple: create a connection to database, formulate and
execute query, read results.  The amount of data  per row fetched is on
average 90 bytes.  Again, if you look at my previous posting you can see
that the query execution time is great - reading the rows is terrible.
Similar results are seen in a C++ program that uses DbTools and oracle OCI
driver.



I was just kidding about Access - obviously there is no comparison.  I am,
however, using PostgreSql on Linux and have no problem executing queries
that move more data than my NT queries in microseconds.  I really think that
I have a gross parameter error that has something to do with reading the
result set out of the database.



import java.sql.*;


public class DbTestA


{


   // Start of driver


   //


   public static void main(String[] args)
   {

     try


     {


       DriverManager.registerDriver (new oracle.jdbc.driver.OracleDriver
());
       String[] Criteria = {"WILL", "ALA", "FRA","BAI"};

       PartyName theTest = new PartyName();
       for (int ii = 0; ii < Criteria.length; ii++)
       {
          theTest.setCriteria(Criteria[ii]);
          theTest.start();
       }
     }
     catch (Exception e)


     {


        System.out.println("Failed to initial test driver: " + e);
     }





   }


}


////////////////////////////////////////////////////////////////////////////
////////
// One inner class per test scenario
////////////////////////////////////////////////////////////////////////////


////////


class PartyName


{


  private String m_Criteria;


  private Connection con;



  public PartyName() throws Exception


  {


   DriverManager.registerDriver (new oracle.jdbc.driver.OracleDriver ());
   con = DriverManager.getConnection ("jdbc:oracle:oci8:@beteldev","orion",
"orion");


   System.out.println("Made the connection");
   System.out.println(con.getMetaData());
  }




  public void setCriteria(String theCriteria)
  {


   m_Criteria = theCriteria;


  }




  public void start()


  {

  //
  // Execute Query
  //




   try


   {



     ResultSet dbResults = null;


     Statement stmt = con.createStatement();
     String SqlStmt =   "select * from name where ptysurnm like '" +
m_Criteria + "%'";
     System.out.println("Executing :" + SqlStmt);

     // time how long it takes to execute the query
     long queryTime = System.currentTimeMillis();
     dbResults = stmt.executeQuery(SqlStmt);
     queryTime = (System.currentTimeMillis() - queryTime);

     // Time how long it takes to drain the reader
     long drainTime = System.currentTimeMillis();
     long recCnt = 0;
     String sColumn;
     try


     {


        while(dbResults.next())
        {
          recCnt++;

          try


            sColumn = dbResults.getString("NAMEID");
            sColumn = dbResults.getString("PTYSURNM");
            sColumn = dbResults.getString("PTYFIRSTNM");
            sColumn = dbResults.getString("PTYSUFFIXNM");
            sColumn = dbResults.getString("PTYSALUTNDE");
            sColumn = dbResults.getString("PTYTITLEDE");
            sColumn = dbResults.getString("PTYMIDDLENM");
            sColumn = dbResults.getString("BusinessNm");
          }
          catch (Exception e)
          {
             System.out.println("getString Error: " + e);
          }
        }
     }
     catch (Exception e)


     {


        System.out.println("while(dbResults.next()) Error: " + e);
     }

     drainTime = System.currentTimeMillis() - drainTime;
     System.out.println("Criteria: " + m_Criteria);
     System.out.println("Query Time: " + queryTime);
     System.out.println("Drain Time: " + drainTime);
     System.out.println("Record Count: " + recCnt);

System.out.println("=================================================");





  }


  catch (Exception e)


  {


     System.out.println(" executeQuery: Error: " + e);
  }



  }


}



mpir_at_compuserve.com wrote in message <7gnjvm$rgf$1_at_nnrp1.dejanews.com>...
>PMJI, but there are some environmental factors that can cause a major
delay:

>1-swapping memory.  I did not see what is doing the retrieval, sga size vs
>available ram, etc. but that kind of delay can happen if the system has
>started swapping buffers.
>
>2-Swapping can be aggrevated or caused if the i/o is to the same disk, that


is


>if you are writing to a file that is on the same disk as the db, etc. This
is


>particularly true if the swapping is happening within Oracle (db block
buffers

>in SGA vs PGA buffers)
>
>3-You say you have no network but are NT. You may be running locally, but


NT

>is still subject to assorted network and other priority interrupts if your
>machine is on a network.
>
>4-How big are the rows?  1000 5K rows may take 5 seconds, but 1000 5 byte


rows

>shouldn't.  NT's screen displays are not the fastest for text modes.
>
>In article <7gnemr$rho7_at_amber.alltel.com>,
>  "MScheuter" <mike.scheuter_at_alltel.com> wrote:
>> Thanks for the response.
>>
>> The query is essentially:
>> select * from CName where LastName like 'Nec%'
>> Again the query execution time is great, in the range of 180 ms.  The


time


>> it takes to retrieve what I consider a small amount of data, about 1000
>> rows, is terrible.  Is it reasonable for oracle to take 5000 ms to send
back


>> to a program 1000 rows of data with no network in the picture?  I think
not

>> since this same operation is MS Access can once again be measured in the
>> hundreds of milliseconds.
>>
>> I tend to think that there is a gross parameter error within the database


on


>> NT.  Our DBA is experienced with Oracle on Unix but not NT and such has
not


>> found anything to tune.  We have been doing traces and cost tracking
through


>> explain plan but this has not yeilded the information that we need.  I
tells

>> us what we already know, that the query (build of the result set) works
>> great.  Explain plan does not tell us what is going on when reading the
>> result set.  Is there additional monitoring options that can be enabled
>> within Oracle?
>>
>> thanks again
>> -mike
>>
>> Sybrand Bakker wrote in message
>> <925837438.21998.0.muttley.d4ee154e_at_news.demon.nl>...
>> >Most likely this is a sql statement tuning issue.
>> >We need to have your statement and details about the tables.
>> >Then: are you using array fetching. This is possible in Pro*C and


without

>> >doubt it is possible in OCI. Fetching a record is the costly operation
>> there
>> >is. Fetch your records in batches of 100 or even 1000. Also makes sure
>> >Oracle traces this session. This will provide useful detail from the


server

>> >side. Make sure sql_trace = true and timed_statistics = true in
>> >init<sid>.ora, bounce the database and see what happens
>> >
>> >Hth,
>> >
>> >Sybrand Bakker, Oracle DBA
>> >
>> >
>> >MScheuter wrote in message <7gn1s6$rho6_at_amber.alltel.com>...
>> >>I have a table that contains customer name information (about 10


fields).


>> >>There are about 1.9 million rows in the table.  The table is index by
the


>> >>last name.  I am writing application code in both C++ using oracle oci
and

>> >>java using again the supplied oracle oci drivers (see oracle web site).
>> In
>> >>a test program I am timing the execution of the select statment and


then

>> >>timing how long it takes to 'read' (or drain) the rows of data from the
>> >>database.  The timing results are as follows:
>> >>
>> >>Rows in Result Set      Query Time (ms)   Read results time (ms)
>> >>2824                             187                            11875
>> >>211                               156
969
>> >>1330                             187                              4984
>> >>1740                               78                              6062


>> >>


>> >>The test program was run on both a workstation using net8 and locally
on


>> >the


>> >>server that is running the database using a local connection (no
network

>> >>involved) and the results were similiar.
>> >>
>> >>The server is a 2 way 200 mhz intell box with 512 meg ram 80 gig hd


space.

>> >>Can someone please explain some areas that I can look at in order to
>> >improve
>> >>the performance of reading the result set?
>> >>
>> >>Thanks
>> >>-mike
>> >>
>> >>
>> >
>> >
>>
>>
>
>--
>Joseph R.P. Maloney, CCP,CSP,CDP
>MPiR, Inc.
>502-451-7404
>some witty phrase goes here, I think.
>
>-----------== Posted via Deja News, The Discussion Network ==----------
>http://www.dejanews.com/       Search, Read, Discuss, or Start Your Own




Received on Wed May 05 1999 - 07:58:02 CDT












Original text of this message













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