optimization in C

From: Jerome Raupach <jraupach(at)intelcom(dot)fr>
To: pgsql-sql(at)postgresql(dot)org
Subject: optimization in C
Date: 2000-08-17 13:23:12
Message-ID: 399BE740.C0664D1E@intelcom.fr
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-sql

This solution isn't good when there are +10000 tuples in the table, it's
slowly...
anybody can help me ? :

string = "SELECT service, noeud, rubrique FROM table" ;
res = PQexec( conn, string.data() ) ;
if ( (! res) || (status = PQresultStatus( res ) != PGRES_TUPLES_OK) )
{
cerr << _ERROR << "Problem SELECT ! " << endl ;
cerr << _ERROR << "Error : " << PQresStatus( status ) << endl ;
cerr << _ERROR << "Error : " << PQresultErrorMessage( res ) << endl ;
PQclear( res ) ;
}
else
{
for (int m=0; m < PQntuples( res ); m++)
{
service = PQgetvalue( resultat1, m, 0 ) ;
noeud = PQgetvalue( resultat1, m, 1 ) ;
rubrique = PQgetvalue( resultat1, m, 2 ) ;

commande = "SELECT SUM(date) FROM table WHERE service='" + service +
"' AND noeud='" + noeud + "' AND rubrique='"+ rubrique + "'" ;
res1 = PQexec( conn, string.data() ) ;
if ( (! res1) || (status = PQresultStatus( res1 ) != PGRES_TUPLES_OK)
)
{
cerr << _ERROR << "Problem SUM ! " << endl ;
cerr << _ERROR << "Error : " << PQresStatus( status ) << endl ;
cerr << _ERROR << "Error : " << PQresultErrorMessage( res1 ) << endl
;
PQclear( res1 ) ;
}
else
{
cout << _TRACE << "SUM ok." << endl ;
PQclear( res1 ) ;
}
}
PQclear( res ) ;
}

Thanks. jerome.

Browse pgsql-sql by date

  From Date Subject
Next Message Andreas Tille 2000-08-17 14:05:53 Beginner problems with functions (Was: Is this the wrong list?)
Previous Message Jesus Aneiros 2000-08-17 12:44:51 Re: Help on some SQL command...