Re: Cast as compound type

["korry" <korry(dot)douglas(at)enterprisedb(dot)com>]

David Fetter wrote:
> I'd like to take a whack at making set-returning functions returning
> SETOF RECORD a little more fun to use.  Let's imagine that we have a
> table foo and a function returning SETOF RECORD that can return foos.
> The call might look something like:
>
> SELECT a, b, c
> FROM f(ROW OF foo)
> WHERE ...;
>
> This would make it much easier and less error-prone to use SETOF
> RECORD.
>   
David, it sounds like you really want to declare the return type of the 
function?  In your above example, you want to say that, in this 
particular invocation, function f() returns a SETOF foo's.  Is that correct?

If you were to create function that returns a RECORD (not a SETOF 
RECORD), you would call it like this:

   SELECT * FROM f() AS (column1 type1, column2 type2, column3 type3);

In your case, I think you want to declare the return type using an 
explicitly defined composite type (possibly a table row); which would 
imply syntax such as:

   SELECT * FROM f() AS (foo);
      or
   SELECT * FROM f() AS (foo.*);

So, it seems like you want the syntax to look more like:

   SELECT a,b,c, FROM f() AS (SETOF foo);

Does that make sense to you?  Your original syntax implied that the "ROW 
OF foo" was somehow related to the function arguments.
              
                     -- Korry


--

 Korry Douglas  <korryd(at)enterprisedb(dot)com>
 EnterpriseDB    http://www.enterprisedb.com