From the Command Line:
Connecting to a Postgres server
psql -h < host > -U < username >
Connect to Database (Once connected to server)
\c < database name >
Read File into Database
psql -h < host > -U < username > -f < filename >
Listing Commands
List Databases
\l
List Tables
\dt
Query all tables in DB
SELECT * FROM INFORMATION_SCHEMA.TABLES
Get row for for a table
SELECT COUNT(*) FROM <table name>;
Get a random row from a table
SELECT * FROM <table name> OFFSET floor(random() * (SELECT COUNT(*) FROM <table name>)) LIMIT 1;
Delete all data from table
TRUNCATE TABLE <table name(s)>;
Delete all data from table AND reset the auto-increment id
TRUNCATE TABLE <table name(s)> RESTART IDENTITY;