Connection Credentials Table

The pg_dist_authinfo table holds authentication parameters used by Citus nodes to connect to one another.

Upon beginning a connection, a node consults the table to see whether a row with the destination nodeid and desired rolename exists. If so, the node includes the corresponding authinfo string in its libpq connection. A common example is to store a password, like 'password=abc123', but you can review the full list of possibilities.

The parameters in authinfo are space-separated, in the form key=val. To write an empty value, or a value containing spaces, surround it with single quotes, e.g., keyword='a value'. Single quotes and backslashes within the value must be escaped with a backslash, i.e., \' and \\.

The nodeid column can also take the special values 0 and -1, which mean all nodes or loopback connections, respectively. If, for a given node, both specific and all-node rules exist, the specific rule has precedence.

SELECT * FROM pg_dist_authinfo;

 nodeid | rolename | authinfo
--------+----------+-----------------
    123 | jdoe     | password=abc123
(1 row)

Connection Pooling Credentials

If you want to use a connection pooler to connect to a node, you can specify the pooler options using pg_dist_poolinfo. This metadata table holds the host, port and database name for Citus to use when connecting to a node through a pooler.

If pool information is present, Citus will try to use these values instead of setting up a direct connection. The pg_dist_poolinfo information in this case supersedes pg_dist_node.

-- how to connect to node 1 (as identified in pg_dist_node)

INSERT INTO pg_dist_poolinfo (nodeid, poolinfo)
     VALUES (1, 'host=127.0.0.1 port=5433');