Re: PATCH: make plpgsql IN args mutable (v1) [REVIEW]

> On Sep 16, 2009, at 12:44 PM, Michael Glaesemann wrote:
>
>> Certainly. I was doing that to have a simple example; obviously you
>> wouldn't write a mod funciton, and you wouldn't do it in plpgsql.
>> There
>> are other case where the lack of mutability in IN parameters causes
>> you
>> to create a throwaway variable.
>
> Have an example at hand? I'd argue that in a case of a function of
> more complexity from a code clarity standpoint you'd want to assign
> to a new variable that describes what the new value reflects.

I can't say I disagree with you from a purist standpoint, but for
porting existing code sometimes it's more efficient to port what you
have without rewriting it. In some of the code I'm looking at porting,
this is a very simple example of a common pattern I'm seeing:

create function create_some_object(pobjectid uuid, psomefkobjectid
uuid) returns uuid as $$
begin
if pobjectid is null then
pobjectid := newid()
end if

if psomefkobjectid is null then
select objectid into psomefkobjectid from somefktable where whatever;
end if

-- create the object
return pobjectid
end;

-Steve