SQL Cross JOIN or Cartesian Product

This type of JOIN returns the cartesian product of rows of from the tables in Join. It will return a table which consists of records which combines each row from the first table with each row of the second table.

Cross JOIN Syntax is,

SELECT column-name-list
from table-name1 
CROSS JOIN 
table-name2;

Example of Cross JOIN

The class table,

ID
NAME
1
abhi
2
adam
4
alex


The class_info table,

ID
Address
1
DELHI
2
MUMBAI
3
CHENNAI


Cross JOIN query will be,
SELECT *
 from class,
 cross JOIN class_info;


The result table will look like,

ID
NAME
ID
Address
1
abhi
1
DELHI
2
adam
1
DELHI
4
alex
1
DELHI
1
abhi
2
MUMBAI
2
adam
2
MUMBAI
4
alex
2
MUMBAI
1
abhi
3
CHENNAI
2
adam
3
CHENNAI
4
alex
3
CHENNAI

SQL Types Of Joins

The following are the types of JOIN that we can use in SQL.

• Inner
• Outer
• Left
• Right

SQL Joins

SQL Join is used to fetch data from two or more tables, which is joined to appear as single set of data. SQL Join is used for combining column from two or more tables by using values common to both tables. JoinKeyword is used in SQL queries for joining two or more tables. Minimum required condition for joining table, is(n-1) where n, is number of tables. A table can also join to itself known as, Self Join.

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