FreeTDS Development Group

[craigs <s.craig AT andronics.com>]

Bill,

'return NO_MORE_ROWS' does take me out of the code segment which is 
exactly what i want, but is it safe to do so.  I know that the insert 
just before i call the return statement also works.  I just want to be 
sure that for some reason all the records in my table aren't being 
searched when i exit as this would slow my programs down, what i mean is 
i dont get a chance to call the following functions after the 'return 
NO_MORE_ROWS'

dbfreebuf(dbconn);
dbclose(dbconn);
dbexit();

Would this have any effect on my number of licences seen as its not 
closing the connection, any other side-effects?

Shaun.

Thompson, Bill D (London) wrote:

> Shaun,
>
> that "return NO_MORE_ROWS" is going to leap right out of this entire
> code segment, n'est-ce pas ?
> ..in which case you'll only call the dbcanquery() after dbnextrow() has
> returned NO_MORE_ROWS
> ..at which point there's no point in calling dbcanquery()
>
> did you mean to code a "break" instead of the "return NO_MORE_ROWS" ?
>
> Also, your table has 2.4 million rows.
> does that mean the query behind this dbresults loop is returning 2.4
> million rows ?
> if so, you should try and cut that number down at source, via your
> query.
> ..unless you have a nice fat network :-)
>
> Bill
>
> -----Original Message-----
> From: freetds-bounces AT lists.ibiblio.org
> [mailto:freetds-bounces AT lists.ibiblio.org] On Behalf Of craigs
> Sent: 10 March 2005 12:03
> To: FreeTDS Development Group
> Subject: Re: [freetds] dbnextrow() question
>
>
> Right having problems with this, i want to exit query when i get what i 
> want, theres over 2.4 millions records in my table so really need to get
>
> this right, can someone advise me if the following code would work.
>
> while ((return_code = dbresults(dbconn)) != NO_MORE_RESULTS)
> {
>             if (return_code == SUCCEED)
>             {
>                        /* Bind results to program variables. */
>                        dbbind(dbconn, 1, NTBSTRINGBIND, 0, (BYTE *)& 
> PlaceName);
>                        dbbind(dbconn, 2, FLT8BIND, 0,
> (BYTE*)&Longitude);
>                        dbbind(dbconn, 3, FLT8BIND, 0,
> (BYTE*)&Latitude);
>                        dbbind(dbconn, 4, NTBSTRINGBIND, 0, (BYTE *)& 
> Country);
>                        dbbind(dbconn, 5, NTBSTRINGBIND, 0, (BYTE *)&
> Town);
>                        dbbind(dbconn, 6, INTBIND, (DBINT)0, (BYTE *)& 
> SweepRadius);
>           
>                        /* Retrieve and print the result rows. */
>                        while (dbnextrow(dbconn) != NO_MORE_ROWS)
>                        {
>                                    tempDist = LatLonDistance( prev_lat,
>
> prev_lon, Latitude, Longitude );
>               
>                                    tempDist = tempDist * 1000; 
> //convert kilometers to meters
>               
>                                    if ( tempDist <= SweepRadius )
>                                    {
>                                            /* Find what i'm looking for
>
> so i call a function to Insert into a table using variables above. */
>                                            InsertRecord(roadsquery);
>                  
>                                            return NO_MORE_ROWS;
>                                    }
>                        }
>                        dbcanquery(dbconn);
>             }
> }
>
> Any help would be much appreciated, thanks.
>
> Shaun.
>
> craigs wrote:
>
>  
>
> > can i do the following using dbcanquery()
> >
> > while (dbnextrow(dbconn) != NO_MORE_ROWS)
> > {
> >    bind results to varialbes
> >
> >         if ( find what i want )
> >         {
> >              do something here
> >               now exit doing the following
> >
> >            dbcanquery(dbconn);
> >         }
> > }
> >
> > will this let me exit the loop correctly with the variables still set?
> >
> >
> >
> > Thompson, Bill D (London) wrote:
> >
> >    
> >
> > > Easy, cowboy.
> > >
> > > well, *might* is right , if you'll excuse the pun - as there is one
> > > circumstance when it wouldn't go wrong.
> > >
> > > On the other hand, I *might* not have had the time to go into all the
> > > gory details :-)
> > >
> > > Yours non-specifically,
> > >
> > > Bill
> > >
> > > -----Original Message-----
> > > From: freetds-bounces AT lists.ibiblio.org
> > > [mailto:freetds-bounces AT lists.ibiblio.org] On Behalf Of Lowden, James
> > >      
> K
>  
>
> > > Sent: 08 March 2005 17:57
> > > To: ml AT freetds.org
> > > Subject: RE: [freetds] dbnextrow() question
> > >
> > >
> > >
> > >
> > >      
> > >
> > > > From: Thompson, Bill D (London)
> > > > Sent: Tuesday, March 08, 2005 6:01 AM
> > > >
> > > > your next call to dblibrary *might* fail with a "results pending"
> > > >        
> type
>  
>
> > > > error though, if you tray and do another operation on the same
> > > >        
> channel
>  
>
> > > >  
> > > >        
> > > What "might"?  *Will* fail, period. 
> > > The code below doesn't tell the server to stop sending rows, and
> > >      
> doesn't
>  
>
> > > tell the library the that the result set was exhausted/cancelled.
> > > db-lib maintains information about the state of the connection, and
> > >      
> will
>  
>
> > > refuse to send another query.  Anything else is a bug. 
> > > The only exception would be if the last row fetched happened also to
> > >      
> be
>  
>
> > > the last row sent, i.e., the last row of the result set.  Some
> > > implementations of db-lib (not FreeTDS, afaik), will note the
> > > end-of-rowset packet and update the internal connection status
> > > automatically.  Others will not do so until dbnextrow returns
> > > NO_MORE_ROWS. 
> > > Am I missing something? 
> > > --jkl
> > >
> > >
> > >
> > >
> > >      
> > >
> > > > -----Original Message-----
> > > > From: freetds-bounces AT lists.ibiblio.org
> > > > [mailto:freetds-bounces AT lists.ibiblio.org] On Behalf Of craigs
> > > > Sent: 08 March 2005 10:58
> > > > To: FreeTDS Development Group
> > > > Subject: Re: [freetds] dbnextrow() question
> > > >
> > > >
> > > > found an easier way of doin it.
> > > >
> > > > while (dbnextrow(dbconn) != NO_MORE_ROWS)
> > > > {
> > > >     if ( find what i want )
> > > >     {
> > > >           do something here
> > > >           now exit doing the following
> > > >
> > > >        return NO_MORE_ROWS; // this will let you exit
> > > >     }
> > > > }
> > > >
> > > >
> > > > Thompson, Bill D (London) wrote:
> > > >
> > > >  
> > > >
> > > >        
> > > >
> > > > > Shaun
> > > > >
> > > > > see dbcanquery() or dbcancel() . dbcanquery looks like exactly what
> > > > >    
> > > > >          
> > > you
> > >
> > >
> > >      
> > >
> > > > > want.
> > > > >
> > > > > -----Original Message-----
> > > > > From: freetds-bounces AT lists.ibiblio.org
> > > > > [mailto:freetds-bounces AT lists.ibiblio.org] On Behalf Of craigs
> > > > > Sent: 04 March 2005 12:19
> > > > > To: FreeTDS Development Group
> > > > > Subject: [freetds] dbnextrow() question
> > > > >
> > > > >
> > > > > Could someone tell me how to exit this loop?  I dont want to run
> > > > >    
> > > > >          
> > > > through
> > > >  
> > > >
> > > >        
> > > >
> > > > > thousands of unnecessary records when i find the one i want.
> > > > >
> > > > > while (dbnextrow(dbconn) != NO_MORE_ROWS)
> > > > > {
> > > > >    if ( find what i want )
> > > > >    {
> > > > >          do something here
> > > > >          now i want to exit out off this loop
> > > > >    }
> > > > > }
> > > > >
> > > > > Shaun
> > > > >    
> > > > >          
> > > -----------------------------------------
> > > The information contained in this transmission may contain privileged
> > > and confidential information and is intended only for the use of the
> > > person(s) named above. If you are not the intended recipient, or an
> > > employee or agent responsible for delivering this message to the
> > > intended recipient, any review, dissemination, distribution or
> > > duplication of this communication is strictly prohibited. If you are
> > >      
> not
>  
>
> > > the intended recipient, please contact the sender immediately by
> > >      
> reply
>  
>
> > > e-mail and destroy all copies of the original message. Please note
> > >      
> that
>  
>
> > > we do not accept account orders and/or instructions by e-mail, and
> > > therefore will not be responsible for carrying out such orders and/or
> > > instructions.
> > > If you, as the intended recipient of this message, the purpose of
> > >      
> which
>  
>
> > > is to inform and update our clients, prospects and consultants of
> > > developments relating to our services and products, would not like to
> > > receive further e-mail correspondence from the sender, please "reply"
> > >      
> to
>  
>
> > > the sender indicating your wishes.  In the U.S.: 1345 Avenue of the
> > > Americas, New York, NY 10105.
> > >
> > >
> > > _______________________________________________
> > > FreeTDS mailing list
> > > FreeTDS AT lists.ibiblio.org
> > > http://lists.ibiblio.org/mailman/listinfo/freetds 
> > > --------------------------------------------------------
> > >
> > > If you are not an intended recipient of this e-mail, please notify 
> > > the sender, delete it and do not read, act upon, print, disclose, 
> > > copy, retain or redistribute it. Click here for important additional 
> > > terms relating to this e-mail.     http://www.ml.com/email_terms/ 
> > > --------------------------------------------------------
> > >
> > > _______________________________________________
> > > FreeTDS mailing list
> > > FreeTDS AT lists.ibiblio.org
> > > http://lists.ibiblio.org/mailman/listinfo/freetds
> > >
> > >
> > >
> > >      
> > _______________________________________________
> > FreeTDS mailing list
> > FreeTDS AT lists.ibiblio.org
> > http://lists.ibiblio.org/mailman/listinfo/freetds
> >    
>
>
> _______________________________________________
> FreeTDS mailing list
> FreeTDS AT lists.ibiblio.org
> http://lists.ibiblio.org/mailman/listinfo/freetds 
> --------------------------------------------------------
>
> If you are not an intended recipient of this e-mail, please notify the sender, delete it and do not read, act upon, print, disclose, copy, retain or redistribute it. Click here for important additional terms relating to this e-mail.     http://www.ml.com/email_terms/ 
> --------------------------------------------------------
>
> _______________________________________________
> FreeTDS mailing list
> FreeTDS AT lists.ibiblio.org
> http://lists.ibiblio.org/mailman/listinfo/freetds
>