Обсуждение: Clarification on materialized view restriction needed

Поиск
Список
Период
Сортировка

Clarification on materialized view restriction needed

От
Ashutosh Bapat
Дата:
Hi All,
I want to create a materialized view as the output of a plpgsql function returning a set of rows. But that function creates temporary tables and thus can not be used for creating materialized view as per the documentation at http://www.postgresql.org/docs/9.3/static/sql-creatematerializedview.html.
"This query will run within a security-restricted operation; in particular, calls to functions that themselves create temporary tables will fail."

I tried to understand what is "security-restricted operation", and didn't find any definition of this term or any listing as to "these are security-restricted operations ...". I am wondering what are other restrictions on the queries whose results can be used to create materialized views.


--
Best Wishes,
Ashutosh Bapat
EntepriseDB Corporation
The Postgres Database Company

Re: Clarification on materialized view restriction needed

От
Noah Misch
Дата:
On Tue, Aug 27, 2013 at 01:57:49PM +0530, Ashutosh Bapat wrote:
> I want to create a materialized view as the output of a plpgsql function
> returning a set of rows. But that function creates temporary tables and
> thus can not be used for creating materialized view as per the
> documentation at
> http://www.postgresql.org/docs/9.3/static/sql-creatematerializedview.html.
> "This query will run within a security-restricted operation; in particular,
> calls to functions that themselves create temporary tables will fail."
> 
> I tried to understand what is "security-restricted operation", and didn't
> find any definition of this term or any listing as to "these are
> security-restricted operations ...". I am wondering what are other
> restrictions on the queries whose results can be used to create
> materialized views.

The semantics of a security-restricted operation remain undocumented.  You can
witness the list of restrictions by searching for callers of
InSecurityRestrictedOperation().  Here is the current list for core code:

- CREATE TEMP TABLE
- SET ROLE
- SET SESSION AUTHORIZATION
- CLOSE
- PREPARE
- DEALLOCATE
- LISTEN
- UNLISTEN
- DISCARD

-- 
Noah Misch
EnterpriseDB                                 http://www.enterprisedb.com



Re: Clarification on materialized view restriction needed

От
Ashutosh Bapat
Дата:
I would be good, if this set gets documented, lest users will be confused. Can you point me to relevant sections of document? I can add this documentation.


On Wed, Aug 28, 2013 at 10:12 AM, Noah Misch <noah@leadboat.com> wrote:
On Tue, Aug 27, 2013 at 01:57:49PM +0530, Ashutosh Bapat wrote:
> I want to create a materialized view as the output of a plpgsql function
> returning a set of rows. But that function creates temporary tables and
> thus can not be used for creating materialized view as per the
> documentation at
> http://www.postgresql.org/docs/9.3/static/sql-creatematerializedview.html.
> "This query will run within a security-restricted operation; in particular,
> calls to functions that themselves create temporary tables will fail."
>
> I tried to understand what is "security-restricted operation", and didn't
> find any definition of this term or any listing as to "these are
> security-restricted operations ...". I am wondering what are other
> restrictions on the queries whose results can be used to create
> materialized views.

The semantics of a security-restricted operation remain undocumented.  You can
witness the list of restrictions by searching for callers of
InSecurityRestrictedOperation().  Here is the current list for core code:

- CREATE TEMP TABLE
- SET ROLE
- SET SESSION AUTHORIZATION
- CLOSE
- PREPARE
- DEALLOCATE
- LISTEN
- UNLISTEN
- DISCARD

--
Noah Misch
EnterpriseDB                                 http://www.enterprisedb.com



--
Best Wishes,
Ashutosh Bapat
EntepriseDB Corporation
The Postgres Database Company

Re: Clarification on materialized view restriction needed

От
Robert Haas
Дата:
On Wed, Aug 28, 2013 at 1:40 AM, Ashutosh Bapat
<ashutosh.bapat@enterprisedb.com> wrote:
> I would be good, if this set gets documented, lest users will be confused.
> Can you point me to relevant sections of document? I can add this
> documentation.

I think it's your job to look at the documentation and determine where
this would best fit, not Noah's to go decide that for you.

...Robert