jdbc Introduction (SQL)


Since Java 6, the recommended way to access an SQL-based database in Java is via the JDBC(Java DataBase Connectivity) API.

This API comes in two packagages: java.sql and javax.sql.

JDBC defines database interactions in terms of Connections and Drivers.

A Driver interacts with the database, and provides a simplified interface for opening and managing connections. Most database server varieties (PostgreSQL, MySQl, etc.) have their own Drivers, which handle setup, teardown, and translation specific to that server. Drivers are usually not accessed directly; rather, the interface provided by the DriverManager object is used instead.

The DriverManager object is essentially the core of JDBC. It provides a (mostly) database-agnostic interface to create Connections. For older versions of the JDBC API, database-specific Drivers had to be loaded before DeviceManager could create a connection to that database type.

A Connection is, as the name implies, a representation of an open connection to the database. Connections are database-agnostic, and are created and provided by the DriverManager. They provide a number of 'shortcut' methods for common query types, as well as a raw SQL interface.