You can connect to MySQL, PostgreSQL, Oracle, and SQLite databases without having to install the corresponding database engine's client connectivity libraries.
For MySQL, you have the option to connect directly, or use the libmysqld.dll client library.
Connections to PostgreSQL databases are always made without the need for any client libraries to be installed.
For Oracle, you can connect directly to a server without using the Oracle Call Interface (OCI) library. However, there are some limitations to using the direct mode, the details of which can be found here.
For SQLite, you can choose to connect directly, or use the sqlite3.dll file if you have one.
