SQL JOINING is so powerful because the
SQL JOIN allows you to take
Data Across Multiple Sources and
Compare it to make changes with little effort on your end that why
SQL JOIN is really so Powerful in SQL.
Actually, SQL JOINS are a costly database operation because they require the creation of a cartesian product in memory that means a virtual table is created in memory that has a number of rows that is a multiplication of the number of rows from all the tables that you are joining.
The SQL JOIN used to combines multiple columns from one or more tables in a relational database.
TYPE OF SQL JOIN IN DATABASE
- INNER JOIN
- LEFT JOIN or LEFT OUTER JOIN
- RIGHT JOIN or RIGHT OUTER JOIN
- FULL JOIN