Types of Joins in Oracle SQL

When writing SQL queries in Oracle, there are several types of joins that you can use to retrieve data from multiple tables. The main types of joins in Oracle SQL are:

• Inner Join: Returns only the rows that have matching values in both tables.
• Left Outer Join: Returns all the rows from the left table and the matched rows from the right table. If there is no match, the result is NULL values in the columns of the right table.
• Right Outer Join: Returns all the rows from the right table and the matched rows from the left table. If there is no match, the result is NULL values in the columns of the left table.
• Full Outer Join: Returns all the rows when there is a match in either the left or right table. If there is no match, the result is NULL values in the columns of the other table.
• Cross Join: Returns the Cartesian product of the two tables, resulting in all possible combinations of rows.

Each type of join serves a different purpose and can be used based on the specific requirements of your query. Understanding the differences between these join types is essential for efficient data retrieval in Oracle SQL.