Thread

A dillema ...

Mario Jorge Nunes Filipe <mjnf@neptuno.sc.uevora.pt> — 1999-03-03T17:21:03Z

Hi

i have a table with the following schema :

Table    = epoca
+---------------------------+----------------------------------+-------+
|              Field        |              Type                | Length|
+---------------------------+----------------------------------+-------+
| codigo                    | int4                             |     4 |
| descricao                 | varchar()                        |    20 |
+---------------------------+----------------------------------+-------+

and another with 

Table    = aluno_inscricao
+---------------------------+----------------------------------+-------+
|       Field               |              Type                | Length|
+---------------------------+----------------------------------+-------+
| numero_aluno              | int4                             |     4 |
| codigo_disciplina         | int4                             |     4 |
| ano_lectivo               | char()                           |    10 |
| epoca                     | int4                             |     4 |
| semestre                  | bool                             |     1 |
+---------------------------+----------------------------------+-------+

The field epoca is an "index" to the table epoca.

The table epoca has :

sac=> select * from epoca;
codigo|descricao
------+-------------------
     1|Normal
     2|Especial
     3|Recurso
     6|Recurso Antecipado
     4|Melhoria E. Normal
     5|Melhoria E. Recurso       

when selecting from instancia_disciplina for a particular
codigo_disciplina i get :

sac=> select distinct epoca from aluno_inscricao where
codigo_disciplina=671;
epoca
-----
    1
    3
    4
    5
    6          

Now if i want to get codigo and descricao from epoca according to the
results above i would do:

sac=> select distinct e.codigo, e.descricao from epoca e,
instancia_disciplina i where i.epoca=e.codigo and
i.codigo_disciplina=671;
codigo|descricao
------+-------------------
     1|Normal
     3|Recurso
     5|Melhoria E. Recurso
     6|Recurso Antecipado     

Why doesn't codigo=4 show up, since before the join it did.

I tryed this both on 6.4 and 6.3.2 same results

THanks
--
        Mario Filipe 
        mjnf@uevora.pt
        http://neptuno.sc.uevora.pt/~mjnf