table called 'configuration' cannot be dropped

I am running Postgresql version 9.5.14 on Ubuntu linux 16.04.
My schema defines a table called configuration.
From psql:
# \d configuration
Table "public.configuration"
Column | Type | Modifiers
----------------+------------------------+-----------
parametername | character varying(64) | not null
parametervalue | character varying(256) |
Indexes:
"configuration_pkey" PRIMARY KEY, btree (parametername)

PROBLEM:
When in psql, I type:
# DROP TABLE configuration;

psql just hangs. No further output from psql.
If I hit CTRL-C, it responds as expected with:

^CCancel request sent
ERROR: canceling statement due to user request

But why is psql stuck on the DROP statement?
Is configuration a reserved word or pre-defined table?
Do I need to rename the table?

Thanks,
Dan McCue

pá 8. 3. 2019 v 16:51 odesílatel Daniel McCue <dmccue128(at)gmail(dot)com> napsal:

> I am running Postgresql version 9.5.14 on Ubuntu linux 16.04.
> My schema defines a table called configuration.
> From psql:
> # \d configuration
> Table "public.configuration"
> Column | Type | Modifiers
> ----------------+------------------------+-----------
> parametername | character varying(64) | not null
> parametervalue | character varying(256) |
> Indexes:
> "configuration_pkey" PRIMARY KEY, btree (parametername)
>
> PROBLEM:
> When in psql, I type:
> # DROP TABLE configuration;
>
> psql just hangs. No further output from psql.
> If I hit CTRL-C, it responds as expected with:
>
> ^CCancel request sent
> ERROR: canceling statement due to user request
>
> But why is psql stuck on the DROP statement?
> Is configuration a reserved word or pre-defined table?
> Do I need to rename the table?
>

postgres=# create table public.configuration(xx int);
CREATE TABLE

postgres=# drop table public.configuration ;
DROP TABLE

you can see, the name is not reserved. Probably some queries in some long
transactions holds a locks on this table.

you should to check locks

https://stackoverflow.com/questions/26489244/how-to-detect-query-which-holds-the-lock-in-postgres

Pavel

> Thanks,
> Dan McCue
>
>

Thank you Pavel! This is very helpful. You are correct that it was a lock
problem.
I appreciate the help. My problem is resolved now.
Cheers,
Dan

On Fri, Mar 8, 2019 at 10:55 AM Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>
wrote:

>
>
> pá 8. 3. 2019 v 16:51 odesílatel Daniel McCue <dmccue128(at)gmail(dot)com>
> napsal:
>
>> I am running Postgresql version 9.5.14 on Ubuntu linux 16.04.
>> My schema defines a table called configuration.
>> From psql:
>> # \d configuration
>> Table "public.configuration"
>> Column | Type | Modifiers
>> ----------------+------------------------+-----------
>> parametername | character varying(64) | not null
>> parametervalue | character varying(256) |
>> Indexes:
>> "configuration_pkey" PRIMARY KEY, btree (parametername)
>>
>> PROBLEM:
>> When in psql, I type:
>> # DROP TABLE configuration;
>>
>> psql just hangs. No further output from psql.
>> If I hit CTRL-C, it responds as expected with:
>>
>> ^CCancel request sent
>> ERROR: canceling statement due to user request
>>
>> But why is psql stuck on the DROP statement?
>> Is configuration a reserved word or pre-defined table?
>> Do I need to rename the table?
>>
>
>
> postgres=# create table public.configuration(xx int);
> CREATE TABLE
>
> postgres=# drop table public.configuration ;
> DROP TABLE
>
> you can see, the name is not reserved. Probably some queries in some long
> transactions holds a locks on this table.
>
> you should to check locks
>
>
> https://stackoverflow.com/questions/26489244/how-to-detect-query-which-holds-the-lock-in-postgres
>
> Pavel
>
>
>
>> Thanks,
>> Dan McCue
>>
>>