Обсуждение: SQL query not returning the value expected !!!!!!!!!!!!!!!!!!
Hi if you take a look at the following query's you can see that the third query should logically return 043219
but instead it's not returning any rows ?? What's happening ??????????????
but instead it's not returning any rows ?? What's happening ??????????????
dragon=> SELECT cod_etu from parcours_v where cod_etu = '043219';
cod_etu
---------
(0 rows)
cod_etu
---------
(0 rows)
dragon=> SELECT cod_etu from parcours_hors_cursus_v where cod_etu = '043219';
cod_etu
---------
043219
(1 row)
cod_etu
---------
043219
(1 row)
dragon=> SELECT cod_etu from parcours_hors_cursus_v where cod_etu ='043219' and cod_etu not in (select cod_etu from parcours_v);
cod_etu
---------
(0 rows)
cod_etu
---------
(0 rows)
On Mon, 10 Nov 2003, Najib Abi Fadel wrote: > Hi if you take a look at the following query's you can see that the > third query should logically return 043219 but instead it's not > returning any rows ?? What's happening ?????????????? Are there any NULLs in parcours_v.cod_etu? NOT IN works oddly when combined with NULLs.
thanx this was the problem : the null values .... ----- Original Message ----- From: "Stephan Szabo" <sszabo@megazone.bigpanda.com> To: "Najib Abi Fadel" <nagib.abi-fadel@usj.edu.lb> Cc: "generalpost" <pgsql-general@postgresql.org> Sent: Monday, November 10, 2003 07:58 PM Subject: Re: [GENERAL] SQL query not returning the value expected !!!!!!!!!!!!!!!!!! > > On Mon, 10 Nov 2003, Najib Abi Fadel wrote: > > > Hi if you take a look at the following query's you can see that the > > third query should logically return 043219 but instead it's not > > returning any rows ?? What's happening ?????????????? > > Are there any NULLs in parcours_v.cod_etu? NOT IN works oddly when > combined with NULLs. > > ---------------------------(end of broadcast)--------------------------- > TIP 6: Have you searched our list archives? > > http://archives.postgresql.org