Re: Oracle outer join porting question

> -----Original Message-----
> From: Marko Asplund [mailto:aspa(at)kronodoc(dot)fi]
> Sent: Wednesday, January 15, 2003 4:31 PM
> To: pgsql-sql(at)postgresql(dot)org
> Subject: [SQL] Oracle outer join porting question
>
>
>
> i'm trying to port an existing application from Oracle8i to
> PostgreSQL but
> i'm having problems understanding a certain outer join query
> type used in
> the application. the query includes a normal outer join
> between two tables
> but also uses outer join syntax to join a table with a
> constant. here's a
> simplified version of the query:
>
> SELECT doc.id,doc.title,sub.user_id,sub.operation
> FROM document doc, document_subscription sub
> WHERE 6 = sub.user_id(+) AND sub.document_id(+) = doc.id;
>
> what does the '6 = sub.user_id(+)' condition exactly do in
> this query?
> how would this be translated SQL92 join syntax used by PostgreSQL?
>
> i've tried converting it to:
>
> SELECT doc.id,doc.title,sub.user_id,sub.operation
> FROM document doc LEFT OUTER JOIN document_subscription sub
> ON sub.document_id = doc.id
> WHERE (sub.user_id = 6 OR sub.user_id IS NULL);
>
> but this query is missing the rows in the documents table which have a
> corresponding document_subscription row with 'not user_id = 6'.
>

Try this:

SELECT doc.id,doc.title,sub.user_id,sub.operation
FROM document doc LEFT OUTER JOIN document_subscription sub
ON sub.document_id = doc.id AND sub.user_id = 6;

Tambet