How to change max_connections for Postgres through SQL command

问题

We have a hosted PostgreSQL, with no access to the system or *.conf files.

I do have a admin access and can connect to it using Oracle SQL developer. Can I run any command to increase the max_connections. All other parameters seems to be ok shared mem and buffers can hold more connections so there is not problem there.

回答1:

Changing max_connection parameter needs a Postgres restart

Commands

1. Check max_connection just to keep current value in mind

   SHOW max_connections;
   

2. Change max_connection value

   ALTER SYSTEM SET max_connections TO '500';
   

3. Restart PostgreSQL server

回答2:

Apparently, the hosted Postgres we are using does not provide this option. (compose.io)

So the work around is to use a pgbouncer to manage you connections better.

来源：https://stackoverflow.com/questions/36085499/how-to-change-max-connections-for-postgres-through-sql-command