MYSQL LEFT JOIN

The LEFT JOIN will return all the records from the left table and the matched records from the right table.

Syntax for LEFT JOIN

SELECT column_name(s)
FROM table_name_1
LEFT JOIN table_name_2
ON table_name_1.column_name = table_name_2.column_name;

Assume the table employees with the following data.

empno name age department_id location salary emp_type_id
1 Andrew 30 4 India 100000 2
2 Beslin 29 3 India 90000 1
3 Joanna 23 2 USA 500000 1
4 Tianna 22 4 Canada 500000 1
5 Ani 31 4 USA 700000

Then the `employeetype' with the following data

emp_type_id emp_type
1 Full-Time
2 Contract

Example

select employees.name,employees.location,employeetype.emp_type from employees 
left join employeetype
on employees.emp_type_id= employeetype.emp_type_id;

In the above example, the employee table is the left table which will return all the records and the employeetype is the right table which returns the matched records and unmatched records value will be null.
Output

name location emp_type
Andrew India Contract
Beslin India Full-Time
Joanna USA Full-Time
Tianna Canada Full-Time
Ani USA

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