What causes SQL exception ? How it can be handled ? Explain with example.

 SQL exceptions can occur either if the driver is missing or information about the database is wrong or the SQL query is wrong.

SQL exception can be handled by utilizing the information available from the Exception object, which can be caught with an exception.

Example

import java.sql.*;

public class DemoSQLException {

static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";

static final String DB_URL = "jdbc:mysql://localhost/emp";

static final String user = "root";

static final String pass = "$Arjun12";

public static void main(String[] args) {

Connection connection = null;

PreparedStatement statement = null;

try {

Class.forName(JDBC_DRIVER);

connection = DriverManager.getConnection(DB_URL, user, pass);

Statement stmt = connection.createStatement();

ResultSet rs = stmt.executeQuery("select employee"); //Invalid SQL Statement

while (rs.next())

System.out.println(rs.getInt(1) + " " + rs.getString(2) );

connection.close();

} catch (SQLException se) {

System.out.println("Invalid SQL Statement");

} catch (ClassNotFoundException se) {

System.out.println("Wrong Class Name");

}

}

}


The output of the above program will be “Invalid SQL Statement” since we are passing the wrong query, Hence SQLException caught the exception and printed the message.

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