JDBC (Java Database Connectivity) is a Java API that allows Java applications to interact with relational databases. It provides a standard interface for connecting to databases, executing SQL queries, and retrieving results. JDBC is an essential part of Java’s database connectivity and is used extensively in Java applications for data retrieval and manipulation. Here are key points about JDBC in Java:

1. Database Drivers: To use JDBC, you need a database driver specific to the database system you’re working with. These drivers, known as JDBC drivers, act as a bridge between your Java application and the database. Different databases require different drivers.

2. Basic Steps:

   • Load Driver: You load the appropriate JDBC driver using Class.forName() to register it with the DriverManager.
   • Establish Connection: You use the DriverManager.getConnection() method to establish a connection to the database.
   • Create Statement: You create a Statement or PreparedStatement object for executing SQL queries.
   • Execute Query: You execute SQL queries using the executeQuery() method for SELECT statements and executeUpdate() for INSERT, UPDATE, DELETE, and other non-query statements.
   • Process Results: You retrieve and process the results of SELECT queries using the ResultSet object.
   • Close Resources: You should close the ResultSet, Statement, and Connection objects when you’re done with them.

3. PreparedStatement: PreparedStatement is a more secure and efficient way to execute SQL queries compared to Statement. It allows you to use parameterized queries, which prevent SQL injection attacks and improve performance.

4. Transactions: JDBC supports database transactions, which allow you to group a series of database operations into a single, atomic unit. You can use the commit() and rollback() methods to manage transactions.

5. Batch Processing: JDBC allows you to execute multiple SQL statements in a batch to improve performance. This is useful for inserting, updating, or deleting multiple records at once.

6. Metadata: You can retrieve metadata about the database, such as table and column information, using JDBC’s DatabaseMetaData and ResultSetMetaData classes.

7. Connection Pooling: In production applications, it’s common to use connection pooling libraries (e.g., Apache DBCP, HikariCP) to efficiently manage database connections and improve performance.