Copy command hangs in poll() function

Hello

As per documentation http://initd.org/psycopg/docs/advanced.html Copy
commands are not supported in asynchronous mode, but this will be probably
implemented in a future release. In pgAdmin4 (open source) we have used
async connection to run the SQL query on PostgreSQL database and uses
poll() function to poll the results. When user runs any *COPY *command
application hangs at poll() function.

If copy command not supported then at least it should not hang the
application. poll() function should return the proper error message.

Can you please provide that fix until support for copy command won't come.

--
*Akshay Joshi*

*Sr. Software Architect *

*Phone: +91 20-3058-9517Mobile: +91 976-788-8246*