Oracle EQUI JOIN

SELECT column_list 
FROM table1, table2....
WHERE table1.column_name =
table2.column_name;

SELECT *
FROM table1 
JOIN table2
[ON (join_condition)] 

SELECT agents.agent_city,customer.last_name,  
customer.first_name 
FROM agents,customer  
WHERE agents.agent_id=customer.customer_id;