How to use insert,update and delete query in drupal6 and drupal7?

INSERT STATEMENT

<?php
  // Drupal 6
  db_query("INSERT INTO {mytable} (intvar, stringvar, floatvar) VALUES (%d, '%s', %f)", 5, 'hello world', 3.14);

  // Drupal 7
  $id = db_insert('mytable')
          ->fields(array('intvar' => 5,'stringvar' => 'hello world','floatvar' => 3.14))
          ->execute();
?>


UPDATE STATEMENT.

<?php
  //Drupal 6
  db_query("UPDATE {node} SET title='%s', status=%d WHERE uid=%d", 'hello world', 1, 5);

  //Drupal 7
  db_update('node')
    ->fields(array('title' => 'hello world', 'status' => 1))
    ->condition('uid', 5)
    ->execute();
?>


DELETE STATEMENT.

<?php
  //Drupal 6
  db_query("DELETE FROM {node} WHERE uid=%d AND created < %d", 5, REQUEST_TIME - 3600);

  //Drupal 7
  db_delete('node')
    ->condition('uid', 5)
    ->condition('created', REQUEST_TIME - 3600, '<')
    ->execute();
?>