Batching in jdbc

with loop no transactions

import java.sql.*;

public class BatchInsertExample {
    public static void main(String[] args) {
        String sourceUrl = "jdbc:mysql://localhost:3306/source_db";
        String sourceUsername = "root";
        String sourcePassword = "password";
        
        String destUrl = "jdbc:mysql://localhost:3306/dest_db";
        String destUsername = "root";
        String destPassword = "password";
        
        try {
            Connection sourceConn = DriverManager.getConnection(sourceUrl, sourceUsername, sourcePassword);
            Connection destConn = DriverManager.getConnection(destUrl, destUsername, destPassword);
            
            Statement stmt = sourceConn.createStatement();
            ResultSet rs = stmt.executeQuery("SELECT * FROM source_table");
            
            PreparedStatement pstmt = destConn.prepareStatement("INSERT INTO dest_table (col1, col2, col3) VALUES (?, ?, ?)");
            int batchSize = 50000;
            int count = 0;
            
            while (rs.next()) {
                pstmt.setInt(1, rs.getInt("col1"));
                pstmt.setString(2, rs.getString("col2"));
                pstmt.setDouble(3, rs.getDouble("col3"));
                
                pstmt.addBatch();
                count++;
                
                if (count % batchSize == 0) {
                    pstmt.executeBatch();
                }
            }
            
            // Execute the remaining batch
            pstmt.executeBatch();
            
            rs.close();
            stmt.close();
            pstmt.close();
            sourceConn.close();
            destConn.close();
            
            System.out.println("Batch insert completed successfully");
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}