How to log PostgreSQL queries?

In your data/postgresql.conf file, change the log_statement setting to 'all'.

Edit

Looking at your new information, I’d say there may be a few other settings to verify:

• make sure you have turned on the log_destination variable
• make sure you turn on the logging_collector
• also make sure that the log_directory directory already exists inside of the data directory, and that the postgres user can write to it.