Re: BUG #5035: cast 'text' to 'name' doesnt work in plpgsqlfunction

2009/9/7 Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>:
> Hello
>
> 2009/9/7 Tomasz Karlik <Tomasz(dot)Karlik(at)ultimo(dot)pl>:
>>
>>
>>>>> Alvaro Herrera <alvherre(at)commandprompt(dot)com> 9/4/2009 7:23 PM >>>
>> tkarlik(at)ultimo(dot)pl wrote:
>>
>>> Without casting function executes much slower:
>>>
>>> CREATE OR REPLACE FUNCTION table_exists(tblname text) RETURNS boolean AS '
>>> DECLARE
>>> exists boolean;
>>> BEGIN
>>>     SELECT 1 INTO exists FROM pg_class WHERE relname = name($1);
>>>     RETURN exists;
>>> END;
>>> ' LANGUAGE 'plpgsql' IMMUTABLE;
>>
>
> it some strange. What version do you use?
>
> on 5.4

sorry 8.4

>
> postgres=# explain select * from pg_class where relname='aaa';
>                                         QUERY PLAN
>
> --------------------------------------------------------------------------------
> -------------
>  Index Scan using pg_class_relname_nsp_index on pg_class  (cost=0.00..8.27 rows=
> 1 width=185)
>   Index Cond: (relname = 'aaa'::name)
> (2 rows)
>
> the casting is implicit.
>
> regards
> Pavel Stehule
>
>> If you're looking for a speedy answer, try a SQL function, not plpgsql.
>>
>>
>> The same issue when using SQL function... However other casting (for example
>> int4->int8) works properly.
>>
>