How to store values of dynamically added rows in database

Question

I have a form in which user can add more fields, as he want...

he can add 1,2,3,.... rows of fields..

the code that I use is here,

<?php
echo '
<form method="post" action="">
   <input type="hidden" name="mod" value="'.$mod.'" />
   <table style="width: 700px">
   <tr>
       <th>Description</th>
       <th>Quantity</th>
       <th>Price</th>
   </tr>';

// Loop to prepare the display of 100 product lines
for ($i=0; $i<100; $i++) {

   if ($text['quantity'][$i] == "") $text['quantity'][$i] = 1;
   if ($text['unit'][$i] == "") $text['unit'][$i] = "0.00";
   // Display only the first line
   if ($nbr_ligne == 0) $nbr_ligne = 1;
   if ($i >= $nbr_ligne) $display = 'style="display:none"';
   echo '
   <tr id="cell'.$i.'" '.$display.'>
       <td>
           <textarea name="text[detail]['.$i.']">'.stripslashes($text['detail'][$i]).'</textarea>
           <br />
           <a href="javascript:void(0)" onclick="javascript:document.getElementById(\'cell'.($i+1).'\').style.display=\'table-row\'; this.style.display=\'none\'">[+]</a>
       </td>
       <td>
           <input name="text[quantity]['.$i.']" id="q'.$i.'" value="" size="4" />
       </td>
       <td>
           <input name="text[unit]['.$i.']" id="u'.$i.'" value="" size="7" /> USD
       </td>
   </tr>';
}

echo '
   </table>
   <input type="submit" name="save" value="Save" />
</form>
';
?>

the fields are adding successfully.

now I want to store the values of these fields in database.

the code I use for this is:

if(isset($_POST['save']))
{
    echo mysql_error($db);


       extract($_POST);
       $insert=mysql_query(" insert into add (description, quantity, price) values ('{$text['detail'][$i]}','{$text['quantity'][$i]}','{$text['unit'][$i]}')") or die("unable to insert"); 
}

but it does not work. plz help me guys. I need it very much.

Answer 1

You need to put the mysql query in a loop if $i is equal to the nr of row added:

if(isset($_POST['save']))
{
for ($e = 1; $e <= $i; $e++) {
$insert=mysql_query(" insert into add (description, quantity, price) values ('".$text['detail'][$e]."','".$text['quantity'][$e]."','".$text['unit'][$e]."')") or die("unable to insert"); 
}
}

Answer 2

The issue here is that $i has not been initialized in the script that you are using to save to the database. You will need to loop through from 0 to 100 and BREAK if a number does not exist. You're also using the reserved keyword add. Use backticks ` on reserved keywords.

extract($_POST);

foreach(range(0,100) as $i){
    if(isset($text['detail'][$i]) && isset(isset($text['quantity'][$i]) && isset(isset($text['unit'][$i])){
         $insert= mysql_query(" INSERT INTO `add` (`description`, `quantity`, `price`) VALUES ('".$text['detail'][$i]."','".$text['quantity'][$i]."','".$text['unit'][$i]."')") or die(mysql_error());
    }
    else{
        break;
    }
}

Not too fond of the way you're looping on inserts, but the above piece of code should work, even though it's clearly not the best solution. A better way would be to create one singular INSERT query that inserts multiple rows:

INSERT INTO example (name, age)
VALUES   ('John', 24),   ('Katrina', 21),   ('Michael', 22),   ('Hui Ling', 25),   ('Catherine', 29)

If you must loop on separate queries, you should use prepared statements for performance reasons.

Other issues:

1. You're open to SQL injection .
2. You're using the mysql functions, which are no longer recommended. Use PDO or mysqli instead.