SELECT column_name(s) FROM table1 INNER JOIN table2 ON table1.column_name=table2.column_name;
The INNER JOIN keyword selects all rows from these tables as long as there is a match between the columns in both tables.
Inner joins are mostly used in the Equi-Joins and Natural Joins. In the EquiJoin, you bridge two tables with a defined column, from left to right as default . Hence,the tables in reference can have the equal-predicate. The natural join is a type of Equi join, where you don't have to know the matching columns.