PHP Update Data of MySQL

After data insert , select and delete , data updation is also necessary for any web application.
Update syntax
update  table_name
set     column1= value1, column2=value2,coulmn_n=value_n
where   column_name=Value ;

and PHP Query would be as follow :
$query = "UPDATE table_name
          SET column1='value1',column2='value2'
          WHERE column_name=any_value";


database : dbtuts
table : users
here i use following details for this tutorial

CREATE DATABASE `dbtuts` ;
CREATE TABLE `dbtuts`.`users` (
`user_id` INT( 10 ) NOT NULL AUTO_INCREMENT PRIMARY KEY ,
`first_name` VARCHAR( 25 ) NOT NULL ,
`last_name` VARCHAR( 25 ) NOT NULL ,
`user_city` VARCHAR( 45 ) NOT NULL
) ENGINE = InnoDB;

i hope you should know that how to select data from database , so i come to the point.
first of all select the data from database table and display it on page.
Suppose following is the data :

data.php


mysql_connect("localhost","root","");
mysql_select_db("dbtuts");
$sql_query="SELECT * FROM users";
$result_set=mysql_query($sql_query);
?>


   
   
First Name

   
Last Name

   
City

   
Edit

   

     if(mysql_num_rows($result_set)>0)
 {
  while($row=mysql_fetch_row($result_set))
  {
   ?>
           
           
           
           
           


           
              }
 }
 else
 {
  ?>
       
       
There's No data found !!!

       
         }
 ?>