SQL Join | Definition , Types
and Examples

SQL Join combines rows from two or more tables.

• When data from more than one table in the database is required, a join condition is used.
• Rows in one table can be joined to rows in another table according to common values existing in corresponding columns, that is, usually primary and foreign key columns.
• To display data from two or more tables, we can write a simple join condition in the WHERE clause.

Syntax:

FROM table1
JOIN_TYPE table2
ON JOIN_CONDITION

Example:

Select * from Employee 
INNER JOIN Department 
ON Employee.departmentID= Department.departmentID

Types Of SQL JOINS

Different types of Joins are :

• • • Cross Join
    • INNER JOIN
    • OUTER JOIN
    • LEFT OUTER JOIN
    • RIGHT OUTER JOIN
    • Self Join