Re: [GENERAL] where clauses and selects

2009-09-08 Thread Tim Landscheidt 
Scott Frankel  wrote:

> Is it possible to perform a select in the where clause of a statement?

> I have a situation where I've got one arm tied behind my
> back:  I can only have a single table in the select and from
> clauses, but the where  clause appears to be freed from that
> restriction.

> Given a statement as follows:

>   SELECT foo.foo_id, foo.name
>   FROM foo, bar
>   WHERE foo.bar_id = bar.bar_id
>   AND bar.name = 'martini';

> I'm looking for a way to recast it so that the select and
> from clauses refer to a single table and the join
> referencing the second table  occurs in the where clause.
> [...]

Something along the lines of:

| SELECT foo.foo_id, foo.name FROM foo WHERE foo.bar_id = (SELECT bar.bar_id 
FROM bar WHERE bar.name = 'martini');

should do the trick.

> I've explored the "where exists" clause, but it's not
> supported by the application toolkit I'm using. AFAIK, I've
> only got access to where ...

Dump it. Seriously. There are so many fine things you can do
with a full-fledged database - you certainly do not want to
be restricted in this regard.

Tim


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[GENERAL] where clauses and selects

2009-09-08 Thread Scott Frankel 


Hello,

Is it possible to perform a select in the where clause of a statement?

I have a situation where I've got one arm tied behind my back:  I can  
only have a single table in the select and from clauses, but the where  
clause appears to be freed from that restriction.


Given a statement as follows:

  SELECT foo.foo_id, foo.name
  FROM foo, bar
  WHERE foo.bar_id = bar.bar_id
  AND bar.name = 'martini';

I'm looking for a way to recast it so that the select and from clauses  
refer to a single table and the join referencing the second table  
occurs in the where clause.  For example, something like this:


  SELECT foo.foo_id, foo.name
  FROM foo
  WHERE (SELECT * FROM foo, bar WHERE ...)
  foo.bar_id = bar.bar_id
  AND bar.name = 'martini';

I've explored the "where exists" clause, but it's not supported by the  
application toolkit I'm using. AFAIK, I've only got access to where ...


Thanks in advance!
Scott


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