Mega Code Archive

 

Categories / Oracle PLSQL Tutorial / Table Joins

 

Performing Inner Joins on Multiple Columns Using SQL92

If your join uses more than one column from the two tables, you provide those columns in your ON clause along with the AND operator. SELECT ... FROM table1 INNER JOIN table2 ON table1.column1 = table2.column1 AND table1.column2 = table2.column2; You can further simplify your query though the USING clause, but only if you're performing an equijoin and the column names are identical. For example, the following query rewrites the previous example with the USING clause: SELECT ... FROM table1 INNER JOIN table2 USING (column1, column2);