How to Retrieve MySQL Database Schema Names Using Java JDBC

How can I obtain a list of MySQL database schema names using Java JDBC?

Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/", "username", "password");

To retrieve a list of database schema names from a MySQL server using Java JDBC, you can make use of the 'DatabaseMetaData' interface. This interface provides comprehensive metadata about the database, including the details of its schema. Below, you will find a step-by-step guide along with example code.

try {
    Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/", "username", "password");
    DatabaseMetaData metaData = connection.getMetaData();
    ResultSet schemas = metaData.getSchemas();

    while (schemas.next()) {
        String schemaName = schemas.getString("TABLE_SCHEM");
        System.out.println("Schema Name: " + schemaName);
    }
} catch (SQLException e) {
    e.printStackTrace();
} finally {
    if (connection != null) try { connection.close(); } catch (SQLException { }
}

Causes

• Incorrect JDBC URL leading to connection failure.
• Using wrong credentials to connect to the database.
• Lack of permission to access database metadata.

Solutions

• Ensure the JDBC URL, username, and password are correct.
• Make sure the database user has permission to view database schemas.
• Use the `DatabaseMetaData.getSchemas()` method to fetch schema information.

Mistake: Not closing the ResultSet or Connection properly.

Solution: Always use try-with-resources statement or explicitly close ResultSet and Connection instances in a finally block.

Mistake: Running the code without sufficient JDBC driver dependency.

Solution: Include the MySQL JDBC driver in your project dependencies.