MYsql Joins

By | March 2, 2016

The join keyword is used in an mysql statement to query data from two or more tables,based on the relationship between certains columns in the tables.

Below are the different types of joins with syntax

1.INNER JOIN-Returns rows when there is at least one match in both tables.

Eg:select column_names from table_name1 INNER JOIN table_name2 ON table_name1.column_name=table_name2.column_name.

2.LEFT JOIN-Return all rows from the left table,even if there is no match in the right table.

Eg:select column_names from table_name1 LEFT JOIN table_name2 ON table_name1.column_name=table_name2.column_name.

3.RIGHT JOIN-Return all the rows from the right table,even if there are no matches in the left table.

Eg:select column_names from table_name1 RIGHT JOIN table_name2 ON table_name1.column_name=table_name2.column_name.

4.FULL JOIN-Return when there is a match in one of the tables

Eg:select column_names from table_name1 FULL JOIN table_name2 ON table_name1.column_name=table_name2.column_name.