Re: Function valid only for one table

Hi Tom,

Am 19.05.2004 19:33 schrieb Tom Lane:
> Martin Knipper <knipper(at)mk-os(dot)de> writes:
>
>>I thought about a mixture of object orientation and a normal table
>>for a relational database.
>>someFunction() is a method for the object/table someTable.
>
> Perhaps you could do what you want with functions accepting table
> rowtypes.
>
> create function someFunction(someTable) returns ...
>
> select someFunction(t.*) from someTable t where ...
> -- works
>
> select someFunction(t.*) from anotherTable t where ...
> -- fails
>
> create function someFunction(anotherTable) returns ...
>
> select someFunction(t.*) from someTable t where ...
> -- still works
>
> select someFunction(t.*) from anotherTable t where ...
> -- now calls the second someFunction()
>
> As of existing releases this doesn't scale well to large tables, because
> passing a whole table row to a function leaks memory intraquery. That
> is fixed for 7.5 though.
>

Thanks for those examples. Can you tell me, if this is something
that is defined in the SQL 92/99/03 Standards ?

Greetings,
Martin