log in on psql console:
sudo -u postgres psql postgres
\q
- quit ini console
\l
- databases
\c mydb
- use this db
\dt
- tables
\d my mytable
- show columns in mytable
log in on psql console:
sudo -u postgres psql postgres
\q
- quit ini console
\l
- databases
\c mydb
- use this db
\dt
- tables
\d my mytable
- show columns in mytable