Update defaul value into database if form field is empty else update inputted value

polarexpress

 
    $message = "No food name entered";
    if(isset($_POST['food_name']) && !empty($_POST['food_name'])){  

    echo $_POST['$message'];
    }else{
    echo $_POST['food_name'];
    }

// if form is submitted with empty field the above syntax should update the data "No food name entered". otherwise, if the form is submitted with user inputted value (example of user inputted value: "cheese", "meet", etc) should be updated into database.

the above should check if the field food_name is null or empty in database (although i already set my database fields to 'NOT NULL') and attempt to insert predefined value "No food name entered" into database when the following form is updated with empty field but unfortunately it doesn't update that predefined value. it can only update user inputted value into database. i can't see any mistake in it.

why the above syntax doesn't serve both the purposes?

the details of the form is as following:

if ((isset($_POST["MM_update"])) && ($_POST["MM_update"] == "formX")) { 

 $message = "No food name entered";
if(isset($_POST['food_name']) && !empty($_POST['food_name'])){  
echo $_POST['$message'];
}else{
echo $_POST['food_name'];
}

$updateSQL = sprintf("UPDATE foodtable SET food_name=%s WHERE food_id=%s",    

                       GetSQLValueString($_POST['food_name'], "text"),
                       GetSQLValueString($_POST['food_id'], "int"));

  mysql_select_db($database_XYZ, $XYZ);
  $Result1 = mysql_query($updateSQL, $XYZ) or die(mysql_error());

  $updateGoTo = "choicefood.php";
  if (isset($_SERVER['QUERY_STRING'])) {
    $updateGoTo .= (strpos($updateGoTo, '?')) ? "&" : "?";
    $updateGoTo .= $_SERVER['QUERY_STRING'];
      }
  header(sprintf("Location: %s", $updateGoTo));
    exit ();
}

<form action="<?php echo $editFormAction; ?>" method="post" name="formX" id="formX">
<table align="center">
  <tr valign="baseline">
    <td align="right" nowrap="nowrap">Update Food Name:</td>
    <td><input type="text" name="food_name" value="" size="32" /></td>
  </tr>
   <tr valign="baseline">
    <td nowrap="nowrap" align="right">
     <input type="hidden" name="MM_update" value="formX" />
      <input type="hidden" name="food_id" value="<?php echo $row_food['food_id']; ?>" />
     </td>
                    <td>
                    <input type="submit" value="Update Food Name" />
                    </td>
                  </tr>
                </table>
              </form>

thanks in advance for any help.

traq

polarexpress;11023941 wrote:

 
    $message = "No food name entered";
    if(isset($_POST['food_name']) && !empty($_POST['food_name'])){  

    echo $_POST['$message'];
    }else{
    echo $_POST['food_name'];
    }

// if form is submitted with empty field the above syntax should update the data "No food name entered". otherwise, if the form is submitted with user inputted value (example of user inputted value: "cheese", "meet", etc) should be updated into database.

actually, you're checking if "food_name" exists and is not empty, and if everything is good, you're ignoring it. If the "food_name" is missing, you try to use it... You should be getting an error (undefined index) in that case.

polarexpress;11023941 wrote:

$updateSQL = sprintf("UPDATE foodtable SET food_name=%s WHERE food_id=%s",    

                       GetSQLValueString($_POST['food_name'], "text"),
                       GetSQLValueString($_POST['food_id'], "int"));

what is GetSQLValueString() (unless it also "quotes" your values, you'll get another error in your SQL statement)? Why don't you use a *_real_escape_string() function?

Also, you should really STOP using ext/mysql. It is deprecated; look into mysqli or pdo instead.

Since you question is about default values in your DB, could you post your table schema?

polarexpress

example of my present table structure is as following:

CREATE TABLE IF NOT EXISTS `foodtable` (
  `food_id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
  `food_name` varchar(100) NOT NULL,
    PRIMARY KEY (`food_id`)
) ENGINE=InnoDB  DEFAULT CHARSET=utf8 AUTO_INCREMENT=2 ;


INSERT INTO `foodtable` (`food_id`, `food_name`) VALUES

(1, 'cheese');

the values of database rows/columns (primary key shall be incremented automatically) are primarily inserted by the users through an insert form. so no form fields shall remain either null or empty (as set to not null and previously populated by insert form) when they attempt to update the value using an update form.

i want to use the code so that the form can update new values if the users want to change these through update form or update a default value in case they submit the blank update form. (i don't want to use server side validation in this case).

yes, i'm well aware about mysql depreciation. thanks for your suggestion. may be i shall replace the site wise code in future.

traq

Give this a try. Backup your rows first.

DROP TABLE IF EXISTS `foodtable`;

CREATE TABLE IF NOT EXISTS `foodtable` (
  `food_id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
  `food_name` varchar(100) NOT NULL DEFAULT 'No food name entered',
    PRIMARY KEY (`food_id`)
) ENGINE=InnoDB  DEFAULT CHARSET=utf8;

polarexpress

why should i do it? what if i drop the table directly using drop button of PhpMyAdmin?

traq

You can use phpmyadmin.

The query is the "direct" route, though. phpmyadmin is indirect.

polarexpress

deleting the table in this case was not a solution.

i wasn't supposed to echo the value of food_name in form's hidden field and i haven't mentioned it in the question of my post.

<input type="hidden" name="food_name" value="<?php echo $row_food['food_name']; ?>" />

the above block of code prevented the form to update the predefined value.

i hope that, this post shall be helpful to many new php learners.

thanks,