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The FDW works with cassandra after changing column names of system schema columns. Last function is not required as per my testing. Please update.

Hi
I have problem to use pgCassandra to connect to remote server

postgres=# SELECT * FROM testtab;
ERROR: Error in python: NoHostAvailable
DETAIL: ('Unable to connect to any servers', {'172.17.0.2': AuthenticationFailed('Remote end requires authentication.',), '172.17.0.3': AuthenticationFailed('Remote end requires authentication.',), '172.17.0.4': AuthenticationFailed('Remote end requires authentication.',)})

Tried usermapping but no success.
CREATE USER MAPPING FOR public SERVER cass_serv2 OPTIONS(username 'cassandra', password 'cassandra');

Source is PG9.5 on Ubuntu 14.04
Target is Cassandra 2.2.1 on Ubuntu 14.04

Connection to Cassandra using cassandra2_fdw and CPP Cassandra driver work fine.
Just the multicorn based pgCassandra.CassandraFDW driver has issue..

cheers
Heiko

I am Using pgCassandra to create FDW tables from Cassandra,

My Application is a real-time monitoring system and continues data will insert in Cassandra and the FDW table also will grow based on that.

But While using this which throws the error Too many open files.

While checking in google I got the reason something like "the socket connections are treated like files and they use file descriptor, which is a limited resource".

While we use FDW, every time which is trying to connect with Cassandra using the PORT 9042? or if we create an FDW table and the data will fetch from the FDW with out communicating the Cassandra through the port 9042?

Can you please suggest and solution for this?

We updated the PostgreSQL version 9.5.0 to 9.5.1,
We face an issue while querying, we got an error as follows

server closed the connection unexpectedly This probably means the server terminated abnormally before or while processing the request. The connection to the server was lost. Attempting reset: WARNING: terminating connection because of crash of another server process DETAIL: The postmaster has commanded this server process to roll back the current transaction and exit, because another server process exited abnormally and possibly corrupted shared memory. HINT: In a moment you should be able to reconnect to the database and repeat your command. Failed.

Can you please help.

I have two tables in Cassandra - activity1 and activity2,

I already created two servers using the following queries

CREATE SERVER server_activity1 FOREIGN DATA WRAPPER multicorn options (
wrapper 'pgCassandra.CassandraFDW',
port '9042',
columnfamily 'activity1',
keyspace 'keyspace',
hosts '192.168.1.1'
);

which is working fine for us, but when I want to connect with the second table here I need to create another server?

CREATE SERVER server_activity2 FOREIGN DATA WRAPPER multicorn options (
wrapper 'pgCassandra.CassandraFDW',
port '9042',
columnfamily 'activity2,
keyspace 'keyspace',
hosts '192.168.1.1'
);

OR Can we use the same server for both the tables (columnfamily)?

Some one pls advice.

Hi,
I have multiple primary key fields in Cassandra. And i need to apply WHERE condition on one of those filed then i am getting the following error,

code=2200 [Invalid query] message=\"Cannot execute this query as it might involve data filtering and thus may have unpredictable performance. If you want to execute this query despite the performance unpredictability, use ALLOW FILTERING

What will be the possible reason?