Thread: pg_tables bug?

<div dir="ltr">I'm playing around with tablespace (postgresq 9.4) and I found out what I believe is a bug in
pg_tables.<br/>Basically if you create a database in a table space X and then you create a table on the database the
tableis created correctly on the tablespace X ( I did a check on the filesystem) however if you do a select on
pg_tablesthe column tablespace for that table is empty and even worst if you dump the DB there is no reporting about
thethe database or table being on that tablespace.<br />Even \d doesn't report that the table is in the tablespace
X.<br/><br />Regards</div> 

On Thu, Dec 17, 2015 at 4:54 PM, Gaetano Mendola <mendola@gmail.com> wrote:
> I'm playing around with tablespace (postgresq 9.4) and I found out what I
> believe is a bug in pg_tables.
> Basically if you create a database in a table space X and then you create a
> table on the database the table is created correctly on the tablespace X ( I
> did a check on the filesystem) however if you do a select on pg_tables the
> column tablespace for that table is empty and even worst if you dump the DB
> there is no reporting about the the database or table being on that
> tablespace.
> Even \d doesn't report that the table is in the tablespace X.

Are you sure you created the table in a tablespace? See for example:
=# create tablespace popo location '/to/tbspace/path';
CREATE TABLESPACE
=# create table aa (a int) tablespace popo;
CREATE TABLE
=# \d aa     Table "public.aa"Column |  Type   | Modifiers
--------+---------+-----------a      | integer |
Tablespace: "popo"
=# select tablename, tablespace from pg_tables where tablename = 'aa';tablename | tablespace
-----------+------------aa        | popo
(1 row)

Regards,
-- 
Michael

Gaetano Mendola <mendola@gmail.com> writes:
> I'm playing around with tablespace (postgresq 9.4) and I found out what I
> believe is a bug in pg_tables.
> Basically if you create a database in a table space X and then you create a
> table on the database the table is created correctly on the tablespace X (
> I did a check on the filesystem) however if you do a select on pg_tables
> the column tablespace for that table is empty and even worst if you dump
> the DB there is no reporting about the the database or table being on that
> tablespace.
> Even \d doesn't report that the table is in the tablespace X.

An empty entry in that column means that the table is in the default
tablespace for the database.  Which it sounds like is what you have
here.  I think it's operating as designed, though you might quibble
with the decision that showing default tablespaces explicitly would
have been clutter.
        regards, tom lane

On 12/18/2015 05:18 PM, Gaetano Mendola wrote:
> From documentation about "CREATE DATABASE name WITH TABLESAPCE = 
> tablespace_name":
>
> tablespace_name
> The name of the tablespace that will be associated with the new 
> database, or DEFAULT to
> use the template database's tablespace. This tablespace will be the 
> default tablespace used
> for objects created in this database. See CREATE TABLESPACE for more 
> information.
>
> I'm sure that my tables are created in the name space but those are 
> not reported either in
> pg_tables, either in pg_dump or by \d.

1. Please don't top-post on the PostgreSQL lists. See 
<http://idallen.com/topposting.html>

2. The system is working as designed and as documented - see the 
comments in the docs on pg_tables. If nothing is shown for the table's 
tablespace then it will be in the default tablespace for the database. 
That's what you're seeing. You appear to be assuming incorrectly that it 
means that the table will be in the system's default tablespace.


cheers

andrew