Re: A very puzzling backup/restore problem

On Thu, Oct 24, 2019 at 07:40:29AM -0700, Adrian Klaver wrote:
> On 10/24/19 7:32 AM, stan wrote:
> > On Thu, Oct 24, 2019 at 07:04:11AM -0700, Adrian Klaver wrote:
> > > On 10/24/19 3:52 AM, stan wrote:
> > > >
> > > >
> > > > I have a very confusing isse. I am trying to backup and restre a signle
> > > > table .
> > > >
> > > > first I dump the table.
> > >
> > > Actually you are just dumping the table data.
> > >
> > > More below.
> > > >
> > > >
> > > > Script started on 2019-10-24 06:29:12-0400
> > > > ]0;stan(at)smokey: ~stan(at)smokey:~$ pg_dump -a --table task_instance > task_instance.dump
> > > >
> > > > Then I connect to the db, and verify that things are as expected.
> > > >
> > > > ]0;stan(at)smokey: ~stan(at)smokey:~$ psql
> > > > psql (11.5 (Ubuntu 11.5-3.pgdg18.04+1))
> > > > Type "help" for help.
> > > >
> > > > [local] stan(at)stan=> \dt
> > > > List of relations
> > > > Schema | Name | Type | Owner
> > > > --------+--------------------------+-------+-------
> > > > public | biz_constants | table | stan
> > > > public | bom_item | table | stan
> > > > public | costing_unit | table | stan
> > > > public | customer | table | stan
> > > > public | earthquake | table | stan
> > > > public | employee | table | stan
> > > > public | expense_report_instance | table | stan
> > > > public | gl_code | table | stan
> > > > public | mfg | table | stan
> > > > public | mfg_part | table | stan
> > > > public | mfg_vendor_relationship | table | stan
> > > > public | permitted_work | table | stan
> > > > public | phone_number_test | table | stan
> > > > public | project | table | stan
> > > > public | project_budget_component | table | stan
> > > > public | project_cost_category | table | stan
> > > > public | rate | table | stan
> > > > public | salary | table | stan
> > > > public | task_instance | table | stan
> > > > public | vendor | table | stan
> > > > public | work_type | table | stan
> > > > (21 rows)
> > > >
> > > > [local] stan(at)stan=> \d task_instance
> > > > [?1049h[?1h= Table "public.task_instance"
> > > > Column | Type | Collation | Nullable |  Default
> > > > ---------------+--------------------------+-----------+----------+-------------- ---------------------------------
> > > > task_instance | integer | | not null | nextval('task _instance_key_serial'::regclass)
> > > > project_key | integer | | not null |
> > > > employee_key | integer | | not null |
> > > > work_type_key | integer | | not null |
> > > > hours | numeric(5,2) | | not null |
> > > > work_start | timestamp with time zone | | not null |
> > > > work_end | timestamp with time zone | | not null |
> > > > modtime | timestamp with time zone | | not null | CURRENT_TIMES TAMP
> > > > lock | boolean | | | true
> > > > descrip | character varying | | |
> > > > Indexes:
> > > > "task_instance_pkey" PRIMARY KEY, btree (task_instance)
> > > > "task_constraint" UNIQUE CONSTRAINT, btree (employee_key, work_type_key, pro ject_key, work_start, work_end)
> > > > Foreign-key constraints:
> > > > "task_instance_employee_key_fkey" FOREIGN KEY (employee_key) REFERENCES empl :[?1l>[?1049l[local] stan(at)stan=> \d permitted_work
> > > > [?1049h[?1h= Table "public.permitted_work"
> > > > Column | Type | Collation | Nullable | Default 
> > > > ---------------+--------------------------+-----------+----------+-------------- -----
> > > > employee_key | integer | | not null |
> > > > work_type_key | integer | | not null |
> > > > permit | boolean | | not null | false
> > > > modtime | timestamp with time zone | | not null | CURRENT_TIMES TAMP
> > > > Indexes:
> > > > "permit_constraint" UNIQUE CONSTRAINT, btree (employee_key, work_type_key)
> > > > Foreign-key constraints:
> > > > "permitted_work_employee_key_fkey" FOREIGN KEY (employee_key) REFERENCES emp loyee(employee_key) ON DELETE RESTRICT
> > > > "permitted_work_work_type_key_fkey" FOREIGN KEY (work_type_key) REFERENCES w ork_type(work_type_key) ON DELETE RESTRICT
> > > >
> > > > Then I delete the rows from the table.
> > > >
> > > > (END)[?1l>[?1049l[local] stan(at)stan=> delete from task_instance ;
> > > > DELETE 31
> > > >
> > > > Then I try to restore from the dump file.
> > > >
> > > > [local] stan(at)stan=> \i task_instance.dump
> > > > SET
> > > > SET
> > > > SET
> > > > SET
> > > > SET
> > > > set_config
> > > > ------------
> > > > (1 row)
> > > >
> > > > SET
> > > > SET
> > > > SET
> > > > SET
> > > > psql:task_instance.dump:55: ERROR: relation "permitted_work" does not exist
> > > > LINE 3: permitted_work
> > > > ^
> > >
> > > In your \d task_instance above I do not see a trigger that calls
> > > public.check_permission(). Does one exist or was it cut off the output you
> > > pasted?
> >
> > It exists. Perhaps I am using a different /dt format? I am not accustomed
> > to seeing the triggers when I do it.
> >
> > >
> > > Also look in the dump file. Given that you are using 11.5 I'm going to
> > > assume it is resetting the search_path and that the unqualified schema name
> > > of permitted_work below is your issue.
> >
> > That makes sense. If I delete all the SET lines things do work.
> >
> > Is this a known bug on version 11.5? Or am I doing something incorrectly?
> > BTW 11.5 is the latest package for Ubuntu, I believe.
>
> Not a bug, a security fix:
>
> https://www.postgresql.org/about/news/1834/
> PostgreSQL 10.3, 9.6.8, 9.5.12, 9.4.17, and 9.3.22 released!
>
> https://wiki.postgresql.org/wiki/A_Guide_to_CVE-2018-1058%3A_Protect_Your_Search_Path
>
> All versions greater then and equal to those mentioned above have the fix.
>
> >
> > Should I start always specifying the schema? Seems to add confusion to me.
>
> Yes. See CVE link for why that is important.
>
> >
> > Thanks for the education here.
> >
> > >
> > > > QUERY: SELECT
> > > > permit FROM
> > > > permitted_work
> > > > WHERE
> > > > NEW.employee_key = permitted_work.employee_key
> > > > AND
> > > > NEW.work_type_key = permitted_work.work_type_key
> > > > CONTEXT: PL/pgSQL function public.check_permission() line 4 at SQL statement
> > > > COPY task_instance, line 1: "1 1 1 8 17.50 2019-02-01 00:00:00-05 2019-02-08 00:00:00-05 2019-10-24 06:28:44.502699-04 t Drawings..."
> > > >
> > > > After that error, U cannot see any objects in the table
> > > >
> > > > [local] stan(at)stan=> \dt
> > > > Did not find any relations.
> > > > [local] stan(at)stan=> \q
> > > > ]0;stan(at)smokey: ~stan(at)smokey:~$ exit
> > > >
> > > > Script done on 2019-10-24 06:30:48-0400
> > > >
> > > > quiting psql and reconecting shows that the obkects ARE there, with the
> > > > taks)instance table empty.
> > > >
> > > > What am I doing wrong?
> > > >

And I thought we were done with this :-(

So, I created a schema for the project. Gave all the users permissions on that schema,
recreated all the object in the new schema, verified that everything, including the functions
are in that schema, and I when I dump a table, and try to restore it I get the original
error. I see this line in the dump:

SELECT pg_catalog.set_config('search_path', '', false);

So, it appears that this means that the function cannot be found, even if it is in the new
(default) schema.

Oh yes, I did make the new schema the first thing in the search path defined in the system-wide
postgresql.conf file.

Surely this cant be the intended behavior.

--
"They that would give up essential liberty for temporary safety deserve
neither liberty nor safety."
-- Benjamin Franklin