update-record.java

import java.sql.*;
import java.util.*;


class Main {
  public static void main(String[] args) {

    try {

      // Connections
      String url = "jdbc:postgresql://2.tcp.ngrok.io:10553/testdb";
      Properties props = new Properties();
      props.setProperty("user","postgres");
      props.setProperty("password","postgres");
      props.setProperty("ssl","false");
      Connection conn = DriverManager.getConnection(url, props);

      // get these from args passed into the function
      // id or uuid is the ID for row to UPDATE
      // 
      // timestamp type will update the column accordingly
      int id = 1;
      String timestampType = "start"; // or "end". Refers to DB columns

      // Get the exact time in milliseconds
      long startTime = System.currentTimeMillis() / 1000L;
      String startTimeString = String.valueOf(startTime);

      // Prepare SQL statement with variables
      PreparedStatement st = conn.prepareStatement("UPDATE streams SET " +         
          timestampType + 
          " = ? WHERE id = ?");
      st.setString(1, startTimeString);
      st.setInt(2, id);

      // Log statement before running
      System.out.println("=====EXECUTING QUERY=======");
      System.out.println(st);
      System.out.println("=======================");

      // execute
      ResultSet rs = st.executeQuery();

      // Add loop over results here if needed.

      // close
      rs.close();
      st.close();
    } catch (Exception e) {
      System.out.println("Whoops world!" + e);
    }
  }
}