Re: Linux file permission for COPY TO SQL command

Hello,

COPY TO  stores the output into a file on the server rather than in your
local where client is running.

Spaces in the file name are actually no issue:

$ psql -h 172.17.0.2 -U postgres -c "COPY (SELECT * FROM pg_class) TO
'/var/tmp/pg_class.       OUT  x'"
Password for user postgres:
COPY 420

... but the output file is on the server - in this example inside a
docker container

postgres(at)7680e256387f:~$ ls -ltr /var/tmp
total 208
...
-rw-r--r-- 1 postgres postgres 49291 Oct 29 16:08 'pg_class.  OUT  x'

Copying to client side can be done with \copy (<query or table>) to
'<output file>';

BR/Pozdrawiam,

Roland

On 10/29/25 01:03, Rob Sargent wrote:
>
>
>> On Oct 28, 2025, at 9:39 AM, Krzysztof <kj(at)limes(dot)com(dot)pl> wrote:
>>
>> 
>>
>> I try to use COPY TO command to copy results of a SELECT but I get
>> this message:
>>
>> ERROR:  could not open file "a file" for writing: Permission denied
>>
>
> Is there really a space in the actual file name. That might get
> tricky. You’re suggesting the file already exists: is that true?
> Directory permissions?
>>
>> User, group and other are granted full permission to this file. What
>> should I do more to get this working?
>>
>> --
>> Pozdrawiam
>> Krzysztof Jasieński