Re: How to drop a temporary view?

2012/4/20 Vincenzo Romano <vincenzo(dot)romano(at)notorand(dot)it>:
> 2012/4/20 Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>:
>> Vincenzo Romano <vincenzo(dot)romano(at)notorand(dot)it> writes:
>>> 2012/4/20 Vincenzo Romano <vincenzo(dot)romano(at)notorand(dot)it>:
>>>> 2012/4/20 Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>:
>>>>> You might be able to use "DROP VIEW pg_temp.foo", which will either
>>>>> drop a temp view of your own session or throw an error if there is none.
>>
>>> It works only if you have created at least one temporary object.
>>> Until that the pg_temp "meta schema" doesn't resolve to a real schema
>>> and the exception is thrown!
>>
>> I didn't say *which* error would get thrown ;-).  If you are checking
>> that you'd need to be prepared for both cases.
>>
>>                        regards, tom lane
>
> ... WHEN OTHERS THEN NULL
>
> should be pretty safe to DROP a VIEW!

There's a somehow weird behavior.
This is what I create (sorry for lowecase):
--
create view timeref as select * from current_timestamp timeref;

create or replace function timeref()
returns void
language plpgsql
volatile
as $l0$
begin
drop view if exists pg_temp.timeref;
exception when others then null;
create or replace temporary view timeref as select
current_timestamp::timestamp with time zone timeref;
end
$l0$;

create or replace function timeref( t text )
returns void
language plpgsql
volatile
as $l0$
begin
execute format( 'create or replace temporary view timeref as select
%L::timestamp with time zone timeref',t );
end
$l0$;
--

Now the run(s):
--
tmp1=# SELECT * from timeref;
timeref
-------------------------------
2012-04-20 18:57:09.340628+02
(1 row)

Time: 0,250 ms
tmp1=# SELECT * from timeref();
timeref
---------

(1 row)

Time: 13,639 ms
tmp1=# SELECT * from timeref();
timeref
---------

(1 row)

Time: 40,494 ms
tmp1=# SELECT * from timeref();
NOTICE: view "timeref" does not exist, skipping
CONTEXT: SQL statement "drop view if exists pg_temp.timeref"
PL/pgSQL function "timeref" line 3 at SQL statement
timeref
---------

(1 row)

Time: 12,048 ms
--

As you can see, the third time I get a NOTICE message I don't get the
first two times.
Everything works fine but this strange thing...