Java Database Connectivity [JDBC]

Java Database Connectivity (JDBC) is an application programming interface (API) for connecting Java applications with databases. It allows developers to access and manipulate databases, including relational databases like MySQL, Oracle, and Microsoft SQL Server.

JDBC provides a standard set of Java classes and interfaces to interact with databases. These classes and interfaces are part of the java.sql and javax.sql packages.

Getting Started with JDBC

To use JDBC, you need to have a basic understanding of SQL and databases. Then, you need to download the JDBC driver for your database management system (DBMS) and include it in your Java classpath.

Here's a simple example to illustrate how to use JDBC in Java:

In the above example, we first load the JDBC driver for MySQL using the `Class.forName` method. Next, we establish a connection to the database using the `DriverManager.getConnection` method.

We then create a 'Statement' object to execute our SQL queries. In this case, we execute a SELECT query to retrieve data from the `users` table.

The results of the query are stored in a `ResultSet` object. We can then use the `next` method to iterate through the rows in the result set and retrieve data using the `getString` and `getInt` methods.

Finally, we close the connection to the database using the `close` method.

JDBC Statement Types

JDBC provides three types of `Statement` objects to execute SQL queries:

• `Statement`: Use this type of statement for simple SQL queries that don't take parameters.

• `PreparedStatement`: Use this type of statement for SQL queries that take parameters. Prepared statements are more efficient than statements because they are precompiled and can be executed multiple times with different parameters.

• `CallableStatement`: Use this type of statement to call stored procedures in a database.

Conclusion

Java JDBC is a powerful and flexible API for accessing databases from Java applications. With its standard set of classes and interfaces, JDBC makes it easy for developers to interact with databases and execute SQL queries. Whether you're working with a simple SQL query or complex stored procedures, JDBC has you covered.