Connect various databases using Oracle SQL Developer

Below steps are used to connect to various databases using Oracle SQL Developer.

1. Install Oracle SQL Developer from the Oracle website here
2. By default, it can be able to connect with Oracle database. So no explanation needed.
3. Before connect to databases, need to configure the drivers for the databases into the Oracle SQL Developer.
4. Go to Tools > Preferences > Third party JDBC drivers, configure all the drivers here.
5. For Microsoft SQL Server, follow below steps to configure.
1. Download jtds jar file from here
2. In SQL Developer, Add entry in the above mentioned page Third party JDBC drivers.
3. Give all credentials in the SQLServer tab and click the Retrieve database which is like in this image 
   
6. For MySQL, follow below steps to configure.
1. Download MySQL connector from here 
2. In SQL Developer, Add entry in the above mentioned page Third party JDBC drivers.
3. Give all credentials in the MySQL tab and click the Retrieve database which is like in this image 
   
7. For PostgreSQL, follow below steps.
1. Download PostgreSQL connector from here
2. In SQL Developer, Add entry in the above mentioned page Third party JDBC drivers.
3. For selecting the database, use host name as  like shown in this image, here test is a database name