Information
On Linux/UNIX, the PostgreSQL client logs most interactive statements to a history file. The default PostgreSQL history file is named .psql_history in the user's home directory.
The PostgreSQL command history should be disabled.
Rationale:
Disabling the PostgreSQL command history reduces the probability of exposing sensitive information, such as passwords, encryption keys, or sensitive data.
Solution
For each OS user on the PostgreSQL server, perform the following steps to implement this setting:
Remove .psql_history if it exists.
rm -f ~<user>/.psql_history || true
Use either of the techniques below to prevent it from being created again:
Set the HISTFILE variable to /dev/null in ~<user>/.psqlrc
cat << EOF >> ~<user>/.psqlrc
set HISTFILE /dev/null
EOF
Create ~<user>/.psql_history as a symbolic to /dev/null.
ln -s /dev/null $HOME/.psql_history
Set the PSQL_HISTORY variable for all users:
sudo echo 'PSQL_HISTORY=/dev/null' >> /etc/environment