Re: empty strings select as null bug
Jeffrey Shaw <[email protected]>
| Newsgroups | gmane.comp.db.tds.freetds |
|---|---|
| Message-ID | <CAJYh908uMJFK1j=UYpjoDaBxLGEN9G5ZOpeWQW8Rs4Yy6hySbQ@mail.gmail.com> |
Hi Geoff, Confirmed! My test for the bug now passes. Jeff On Thu, Jun 11, 2015 at 3:17 AM, Geoff Montee <[email protected]> wrote: > On Wed, Jun 10, 2015 at 10:39 PM, LacaK <[email protected]> wrote: > > > > I am using for testing NULL dbdata(), which should return nil for NULL > data. > > (In my case I know, that column exists) > > > > From Sybase documentation: > > "A NULL BYTE pointer is returned if there is no such column or if the > data > > has a null value. To make sure that the data is really a null value, you > > should always check for a return of 0 from *dbdatlen*." > > > > From Microsoft documentation: > > "A NULL BYTE pointer is returned if there is no such column or if the > data > > has a null value. To make sure that the data is really a null value, > check > > for a return of 0 from *dbdatlen*." > > > > So you can use: dbdata()==nil && dbdatlen()==0 > > > > I decided to go with your test: > > > https://github.com/GeoffMontee/tds_fdw/blob/b5f678cded099f9231473c520cf1dbe8363a470a/src/tds_fdw.c#L1855 > > I think Jeff's bug is fixed. > > It's really good to know that dbdatlen() can return 0 in the case of > an empty string. > > Thanks for your help, everyone! > > Geoff > _______________________________________________ > FreeTDS mailing list > [email protected] > http://lists.ibiblio.org/mailman/listinfo/freetds >