Re: sqlite3 and postgresql

[Bob Rossi]

On Wed, May 21, 2008 at 10:13:41AM -0400, Bob Rossi wrote:
> On Mon, May 19, 2008 at 09:32:07PM -0400, Bob Rossi wrote:
> > On Mon, May 19, 2008 at 08:58:32AM +1000, Bojan Smojver wrote:
> > > On Sat, 2008-05-17 at 09:07 -0400, Bob Rossi wrote:
> > > 
> > > > I've been using sqlite3 dbd for some time now. I find that the function
> > > > apr_dbd_get_row,
> > > >   
> > > > http://apr.apache.org/docs/apr-util/trunk/group___a_p_r___util___d_b_d.html#gd4cdc5f4e8981b93f5a467a8c8a768f1
> > > > is 1 based. That is, 1 is the first row returned from a query. However,
> > > > I just started using postgresql, and I find that apr_dbd_get_row is 0
> > > > based. That is, 0 is the first row returned from the query.
> > > 
> > > This should now be fixed in both the trunk and 1.3.x branch.
> > > 
> > > We really _do_ appreciate your testing and suggestions!
> > 
> > I can confirm that the latest 1.3.x snapshot on linux, for both sqlite3
> > and postgresql use a 1 based row index. I removed my hack, and things
> > work great. I'm going to test windows now, could take some time.
> > (perhaps get results tomorrow).
> 
> OK, I have confirmed 1 bug. If you pass '0' to apr_dbd_get_row, with
> postgresql as the driver, the function returns 0, instead of -1 as it
> should. My unit tests happen to test the cases that should fail, that's
> how I caught this.

With a little more research, I noticed that this is simply an if on an
uninitialized variable.
 230|     if (row == NULL) {
 231|         row = apr_palloc(pool, sizeof(apr_dbd_row_t));
 232|         *rowp = row;
 233|         row->res = res;
 234|         if ( sequential ) {
 235|             row->n = 0;
 236|         }
 237|         else {
 238|             if (rownum > 0) {
 239|                 row->n = --rownum;
 240|             }
 241|         }
 242|     }
 243|     else {
 244|         if ( sequential ) {
 245|             ++row->n;
 246|         }
 247|         else {
 248|             if (rownum > 0) {
 249|                 row->n = --rownum;
 250|             }
 251|         }
 252|     }
 253|
 254+---> if (res->random) {
 255|         if (row->n >= res->ntuples) {
 256|             *rowp = NULL;
 257|             apr_pool_cleanup_run(pool, res->res, clear_result);
 258|             res->res = NULL;
 259|             return -1;
 260|         }
 261|     }

The execution is, 230, 231, 232, 233, 234, 238, 254, 255. On line, 255 
row->n is checked, however, it was never initialized.

Hope this helps.
Bob Rossi