The .psql_history file is naturally used by different DB connections (distinguished by a different combination of host + port + database + user). At least in my multi-database working environment, this leads sometimes to frustration because there are commands that cannot or should not be used by different connections. To solve this, psql could keep a separate command history file for each connection. I will be happy to make this my first contribution to PostgreSQL's code. What do you say?
Regards, Jonathan
