Re: BUG #5776: Unable to create view with parameter in PL/pgsql - Mailing list pgsql-bugs

Hello

2010/12/14 Andrey G. <andvgal@gmail.com>:
> Pavel,
>
> As far as I'm aware, SETOF return creates whole result in memory, what
> has some implications.
>

it's not true for immutable SQL function - look on EXPLAIN

> My intention was to create a temporary view in session, which can be
> used in other processing. Of course, I've found another solution, but
> creating view with parameter dynamically could be a good feature.
>

It's done - SQL immutable function works exactly like you need.

Regards

Pavel Stehule


> Andrey
>
>
>
> 2010/12/14 Pavel Stehule <pavel.stehule@gmail.com>:
>> Hello
>>
>> View must not has a parameter in PostgreSQL. You can use a SRF function:
>>
>> postgres=3D# create or replace function parametrized_view(a int)
>> =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0returns se=
tof foo as $$
>> =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 se=
lect * from foo where a =3D $1;
>> =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0$$ languag=
e sql immutable;
>> CREATE FUNCTION
>> postgres=3D# select * from parametrized_view(10);
>> =C2=A0a
>> ----
>> =C2=A010
>> (1 row)
>>
>> postgres=3D# explain select * from parametrized_view(10);
>> =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0QUERY PLAN
>> --------------------------------------------------------------
>> =C2=A0Index Scan using aa on foo =C2=A0(cost=3D0.00..8.27 rows=3D1 width=
=3D4)
>> =C2=A0 Index Cond: (a =3D 10)
>> (2 rows)
>>
>> Regards
>>
>> Pavel Stehule
>>
>>
>> 2010/12/13 Andrey G. <andvgal@gmail.com>:
>>> It seems my original test, which also includes the EXECUTE approach,
>>> has not come to you in full. EXECUTE statement also fails with
>>> parameter: The test is attached in file.
>>>
>>> psql -q < db/db/pgbug_5776.sql
>>> ERROR:=C2=A0 there is no parameter $1
>>> LINE 1: CREATE VIEW v4 AS SELECT * FROM t1 WHERE some_field =3D $1
>>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 ^
>>> QUERY:=C2=A0 CREATE VIEW v4 AS SELECT * FROM t1 WHERE some_field =3D $1
>>> CONTEXT:=C2=A0 PL/pgSQL function "bug_create_tmp_view_exec_test" line 3=
 at
>>> EXECUTE statement
>>>
>>> Andrey
>>>
>>>
>>> 2010/12/13 Robert Haas <robertmhaas@gmail.com>
>>>>
>>>> On Tue, Nov 30, 2010 at 4:43 PM, Andrey Galkin <andvgal@gmail.com> wro=
te:
>>>> >
>>>> > The following bug has been logged online:
>>>> >
>>>> > Bug reference: =C2=A0 =C2=A0 =C2=A05776
>>>> > Logged by: =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0Andrey Galkin
>>>> > Email address: =C2=A0 =C2=A0 =C2=A0andvgal@gmail.com
>>>> > PostgreSQL version: 9.0.1
>>>> > Operating system: =C2=A0 Debian unstable
>>>> > Description: =C2=A0 =C2=A0 =C2=A0 =C2=A0Unable to create view with p=
arameter in PL/pgsql
>>>> > Details:
>>>> >
>>>> > Below is simple test case. Perhaps, I'm doing something wrong.
>>>>
>>>> You can accomplish what you're trying to do using EXECUTE.
>>>>
>>>> --
>>>> Robert Haas
>>>> EnterpriseDB: http://www.enterprisedb.com
>>>> The Enterprise PostgreSQL Company
>>>
>>>
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>>>
>>
>