JOIN operation performs a join between two tables, excluding any unmatched rows from the first table. From Oracle 9i forward, the
JOIN is equivalent in function to the
INNER JOIN. This operation requires an explicit join clause, as opposed to the
CROSS JOIN and
NATURAL JOIN operators.
select t1.*, t2.DeptId from table_1 t1 join table_2 t2 on t2.DeptNo = t1.DeptNo