LEFT JOIN Keyword
The LEFT JOIN keyword is used to combine two tables and returns all records from the left tables and only matching records from the right tables.
Syntax
SELECT * FROM <TABLE1>
LEFT JOIN <TABLE2> ON <TABLE1>.<COLUMN_NAME>=<TABLE2>.<COLUMN_NAME>
Example
SELECT * FROM Employee
LEFT JOIN Department ON Employee.Dept_Id = Department.Dept_Id
If there are no matching records in the right tables, only the left table value is displayed, and null values are substituted for the right table value.
Summary
The LEFT JOIN clause returns a result set that includes all rows from the left tables and only matching rows from the right tables.