FreeTDS Development Group

[Michael Kimsal <michael AT tapinternet.com>]

Gotta jump in here and say 'help'.

Following this thread, I'm guessing that the latest snapshot (10/22)
should now be able to handle large queries in SQL7.  Whoah wait - nope,
this is TDS7.  OK sorry.

Brian, I'm still using TDS4.2 on SQL7, but queries over 512 bytes die.
Using an older snapshot from September sometime, they work, but, for
example, a 622 byte query is taking 150 milliseconds.  *dozens* of
smaller queries before it are taking less than half that time combined.  :(

Anyone got any ideas?

I changed the 'write.c' references to 512 bytes up to 4096, but that
just breaks everything.  I know there's something I'm missing, and I know this
has been beat to death, but I'd really like to have long queries in SQL7,
with TDS4.2, and have them work quickly.

Thanks all.




Brian Bruns wrote:

> Hi Brandon,
>
> Thanks for taking on of my long overdue TODO items :-)
>
> It looks great. I've just committed the patch to the CVS tree so it should
> be there in a few.
>
> Brian
>
> On Wed, 18 Oct 2000, Brandon M. Reynolds wrote:
>
> > Thanks Brian.  That does solve my problem with large queries, but
> > only with ctlib.  I created a patch for making the dbbuf dynamic
> > in the DBPROCESS structure.  Would you pretty please apply this
> > patch so that long queries work with dblib too?
> >
> > diff -urN freetds/include/sybdb.h freetds.10182000/include/sybdb.h
> > --- freetds/include/sybdb.h   Sat Oct  7 15:32:32 2000
> > +++ freetds.10182000/include/sybdb.h  Wed Oct 18 09:01:02 2000
> > @@ -150,7 +150,8 @@
> >     int             noautofree;
> >     int             more_results; /* boolean.  Are we expecting results? 
> > */
> >     BYTE           *user_data;   /* see dbsetuserdata() and 
> > dbgetuserdata()
> > */
> > -   unsigned char   dbbuf[8192]; /* XXX should be dynamic
> > */
> > +   unsigned char  *dbbuf; /* is dynamic!                   */
> > +   int             dbbufsz;
> >     int             empty_res_hack;
> >     TDS_INT         text_size;
> >     TDS_INT         text_sent;
> > diff -urN freetds/src/dblib/dblib.c freetds.10182000/src/dblib/dblib.c
> > --- freetds/src/dblib/dblib.c Sun Oct  8 22:19:09 2000
> > +++ freetds.10182000/src/dblib/dblib.c        Wed Oct 18 09:17:22 2000
> > @@ -449,8 +449,9 @@
> >       }
> >
> >     dbproc->tds_socket = (void *) tds_connect(login->tds_login);
> > -   dbproc->dbbuf[0]='\0'; /* initialize query buffer */
> > -
> > +   dbproc->dbbuf = NULL;
> > +   dbproc->dbbufsz = 0;
> > +
> >     if(dbproc->tds_socket) {
> >        tds_set_parent( dbproc->tds_socket, dbproc);
> >        tds_add_connection(g_tds_context, dbproc->tds_socket);
> > @@ -465,9 +466,26 @@
> >  }
> >  RETCODE      dbcmd(DBPROCESS *dbproc, char *cmdstring)
> >  {
> > -     /* here is one of those large static buffers that should be malloced
> > -     ** but in the interest of time i kludged :)   */
> > -     strcat(dbproc->dbbuf,cmdstring);
> > +     if(dbproc->dbbufsz == 0) {
> > +             if((dbproc->dbbuf =
> > +                     (unsigned char *)malloc(strlen(cmdstring)+1)) ==
> > NULL) {
> > +                     return FAIL;
> > +             }
> > +             strcpy(dbproc->dbbuf,cmdstring);
> > +             dbproc->dbbufsz = strlen(cmdstring) + 1;
> > +     } else {
> > +     int newsz;
> > +     void *p;
> > +
> > +             newsz = strlen(cmdstring) + dbproc->dbbufsz;
> > +             if((p=realloc(dbproc->dbbuf,newsz)) == NULL) {
> > +                     return FAIL;
> > +             }
> > +             dbproc->dbbuf = (unsigned char *)p;
> > +             strcat(dbproc->dbbuf,cmdstring);
> > +             dbproc->dbbufsz = newsz;
> > +     }
> > +
> >       return SUCCEED;
> >  }
> >  RETCODE dbsqlexec(DBPROCESS *dbproc)
> > @@ -534,6 +552,7 @@
> >               }
> >               free(dbproc->bcp_columns);
> >       }
> > +     dbfreebuf(dbproc);
> >
> >       free(dbproc);
> >          tds_del_connection(g_tds_context, dbproc->tds_socket);
> > @@ -1618,7 +1637,11 @@
> >
> >  void dbfreebuf(DBPROCESS *dbproc)
> >  {
> > -   dbproc->dbbuf[0] = '\0';
> > +     if(dbproc->dbbuf) {
> > +             free(dbproc->dbbuf);
> > +             dbproc->dbbuf = NULL;
> > +     }
> > +     dbproc->dbbufsz = 0;
> >  } /* dbfreebuf()  */
> >
> >  RETCODE dbclropt(DBPROCESS *dbproc,int option, char *param)
> > @@ -1895,7 +1918,7 @@
> >        }
> >        if (! dbproc->noautofree)
> >        {
> > -         dbproc->dbbuf[0]='\0';
> > +                             dbfreebuf(dbproc);
> >        }
> >        result = SUCCEED;
> >     }
> >
>

--
==========================
Michael Kimsal
http://www.tapinternet.com
734-480-9961