Mysql Natural Join

Mysql Natural Join is a specialization of equi-joins. The join compares all columns in both tables that have the same column-name in both tables that have column name in the joined table. The resulting set include only one column for each pair of the same named column.

Understand with Example

The Tutorial illustrate an example from 'Mysql Natural Join'. To grasp this example, we create a table 'roseindia'. The create table is used to construct a table 'roseindia' with field name and their respective data type.

Query to Create Table named roseindia:-

mysql> CREATE TABLE roseindia ( 
            -> Empid int(11),          
             ->firstname varchar(30),  
            -> city varchar(30)        
          -> );
Query OK, 0 rows affected (0.05 sec)

Query to insert data into Table named roseindia:-

The insert into add the records values into table 'roseindia'.

mysql>  insert into roseindia values(01,'Girish','Nainital');
Query OK, 1 row affected (0.02 sec)

mysql>  insert into roseindia values(02,'Komal','Merrut');
Query OK, 1 row affected (0.00 sec)

mysql>  insert into roseindia values(03,'Amit','Lucknow');
Query OK, 1 row affected (0.02 sec)

mysql>  insert into roseindia values(04,'Sandeep','Lucknow');
Query OK, 1 row affected (0.03 sec)

mysql>  insert into roseindia values(06,'AA','Delhi');
Query OK, 1 row affected (0.03 sec)

mysql>  insert into roseindia values(09,'BA','Jaipur');
Query OK, 1 row affected (0.03 sec)

Query to view data of Table named roseindia:-

mysql> select * from roseindia;

Output:-

mysql> select * from roseindia;
+-------+-----------+----------+
| Empid | firstname | city     |
+-------+-----------+----------+
|     1 | Girish    | Nainital |
|     2 | Komal     | Merrut   |
|     3 | Amit      | Lucknow  |
|     4 | Sandeep   | Lucknow  |
|     6 | AA        | Delhi    |
|     9 | BA        | Jaipur   |
+-------+-----------+----------+
6 rows in set (0.00 sec)

Query to Create Table newstrack:-

Now again we create another table 'newstrack'. The createtable is used to construct a table 'newstrack'.

mysql> CREATE TABLE newstrack (
        ->     Empid int(11),          
         ->    firstname varchar(10),  
         ->    email varchar(30) 
          -> );
Query OK, 0 rows affected (0.03 sec)

Query to insert data into Table named newstrack:-

mysql>  insert into newstrack values(01,'Suman','[email protected]');
Query OK, 1 row affected (0.02 sec)

mysql>  insert into newstrack values(02,'Ravi','[email protected]');
Query OK, 1 row affected (0.01 sec)

mysql>  insert into newstrack values(03,'Santosh','[email protected]');
Query OK, 1 row affected (0.01 sec)

Query to view data of Table named newstrack:-

mysql> select * from newstrack;

Output:-

+-------+-----------+------------------+
| Empid | firstname | email            |
+-------+-----------+------------------+
|     1 | Suman     | girish.gmail.com |
|     2 | Ravi      | komal.gmail.com  |
|     3 | Santosh   | Amit.gmail.com   |
+-------+-----------+------------------+
3 rows in set (0.00 sec)

Query to join data of Table's created above using Natural join:-

Now we apply Natural Join to the table 'roseindia' and 'newstrack'. The natural left join in below query returns you the matching records from table 'newstrack' that matches with 'roseindia'.

mysql> SELECT R.FirstName, R.city,R.empid
    ->     FROM roseindia as R
    ->      NATURAL LEFT JOIN newstrack as N;

Output:-

+-----------+----------+-------+
| FirstName | city     | empid |
+-----------+----------+-------+
| Girish    | Nainital |     1 |
| Komal     | Merrut   |     2 |
| Amit      | Lucknow  |     3 |
| Sandeep   | Lucknow  |     4 |
| AA        | Delhi    |     6 |
| BA        | Jaipur   |     9 |
+-----------+----------+-------+
6 rows in set (0.00 sec)

Mysql Natural Join

Mysql Natural Join

Mysql Natural Join

Tutorials