Problems with citusdb+cstore_fdw "cannot copy to foreign table ..."

[Yegor Lukash]

Used this email from this topic

I tried to do citus cluster with cstore_fdw. And I rewrote basic docker image (docker in my repo) for working with ext. It compiled and let to create foreing tables:

postgres=# \d

                List of relations

Schema |    Name     |     Type      |  Owner   

 --------+-------------+---------------+---------- 

 public | impressions | foreign table | postgres

First problem: It I have only one worker - copying failed with error: "ERROR:  could only find 1 of 2 possible nodes"

Second problem: I created two workers and got this error: "ERROR:  cannot copy to foreign table "impressions_102008""

What I do wrong? Can you give me working docker image or link to the article about it?

[Murat Tuncer]

Hey Yegor

I was able to reproduce your problem. It looks like it is something to do with docker image generation. Could you do your testing on single machine cluster mode as outlined in https://docs.citusdata.com/en/v5.1/installation/single_machine_deb.html while we investigate this one have a proper image for testing ?

thanks

Murat

[Yegor Lukash]

Hi, Murat. 

Thanks, I will try it with virtual box.

вторник, 19 июля 2016 г., 9:05:44 UTC+3 пользователь Murat Tuncer написал:

[Murat Tuncer]

you do not have to use virtual box.

You could run multiple postgresql instances on a single machine. You just need to make sure they are using different ports. Document link I sent earlier describes that setup. 

[Yegor Lukash]

I used real server, but problem still actual:

I intalled postgresql and enabled ext cstore_fdw - it works fine. But with citus it did not work anythind I do.

Now I have same config:

# Add settings for extensions here

shared_preload_libraries = 'citus'

shared_preload_libraries = 'cstore_fdw'

And it brokes:

$ psql -p 9700 -c "select * from master_get_active_worker_nodes();"

 

ERROR:  Citus can only be loaded via shared_preload_libraries

HINT:  Add citus to shared_preload_libraries configuration variable in postgresql.conf in master and workers. Note that citus should be at the beginning of shared_preload_libraries.

I think that "beginning" means "topper". Do you have some advice?

Thanks.

вторник, 19 июля 2016 г., 12:24:18 UTC+3 пользователь Murat Tuncer написал:

[Murat Tuncer]

hey

Second assigment of shared_preload_libraries overrides the first one.

please use following

shared_preload_libraries = 'citus, cstore_fdw'

[Yegor Lukash]

Yes you are sure. It is my mistake.

пятница, 22 июля 2016 г., 16:21:58 UTC+3 пользователь Murat Tuncer написал: