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Home -> Community -> Usenet -> c.d.o.misc -> Re: SQL NULL vs '' problem
mikep_at_chemweb.com wrote:
>
> There is either a serious bug in Oracle or I misunderstand how
> SQL/Oracle works (I assume the latter!). I expect the first count to
> be at least 1, and the second count to be 0:
>
> SQLWKS> update my_table
> 2> set
> 3> my_table_row='' where my_other_table_row='jsmith';
> 1 row processed.
> SQLWKS> select count(*) from usr where my_table_row='';
> COUNT(*)
> ----------
> 0
> SQLWKS> select count(*) from usr where my_table_row is null and
> my_other_table_row='jsmith';
> COUNT(*)
> ----------
> 1
> 1 row selected.
>
> Even after a commit, you get the same count results. The value of
> my_table_row before was a variety of values. I thought '' and NULL
> were different values, so why does it set it to NULL and even if they
> were the same value, why does a count of my_table_row='' give 0?
>
> btw I am using
> Oracle7 Server Release 7.3.3.4.0 - Production Release
> With the distributed and parallel query options
> PL/SQL Release 2.3.3.4.0 - Production
> running on NT4
>
> Thanks for any help
>
> Mike
>
> Sent via Deja.com http://www.deja.com/
> Share what you know. Learn what you don't.
null does not equal null under any circumstances...
also '' is the same as null in 7, it is NOT the same in 8
HTH
--
"Some days you're the pigeon, and some days you're the statue." Received on Mon Jul 19 1999 - 08:54:55 CDT
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