使用PHP / MYSQL从数据库中删除行

Question

I am trying to delete my data row from my MySQL db.

Below is the query which prints the result of a table with keywords in them. See this pic to see how my results show up:

I am successfully able to get my data from my addKeywordTable however, I can not get the deletion to take place. Here is my index.php page which shows the input button that gets clicked to activate the deletion:

 <?php
 include 'db.php'; 

 $sql = mysqli_query($con,"SELECT * FROM addKeywordTable ORDER BY 
 Keyword_Name ASC");

 print <<<HERE
 <table id="home">
 HERE;

 while ($row = mysqli_fetch_array($sql))
 {
 $key = $row['Keyword_Name'];

 print <<<HERE
 <tr><td>
 <form method="post" formenctype="multipart/form-data" formmethod="POST" 
      value="Delete"      action="deleteKey.php">
 <tr>
 <input type="hidden" name="sel_key" value="$id">
 <input type="submit" name="delete" value=" Delete " id="deleteKey" > $key
 <hr/></tr>
 </form></td></tr>
     HERE;
 }
     print "</tr></table></body></html>";
  ?>

When you click the "Delete" button, you are taken to the confirm page deleteKey.php which looks like this:

        <?php

    require 'db.php';
    $sel_key = $_POST[sel_key];

    //SQL statement to select information
    $sql = "SELECT * FROM addKeywordTable WHERE keyID = $sel_key";

    //loop through record and get values
    while ($key = mysqli_fetch_array($result)) {
    $id = $key['Keyword_Name'];
    } // end while loop

    $pageTitle = "Delete a Keyword";

    print <<<HERE
    <div id="form1profile">
    <h2>Are you sure you want to delete this record?<br/>
    It will be permanently removed:</h2>

    <ul>
    <li>Keyword Category:<br/></li>
    $key;
    </ul>
    <p><br />
    <form method="post" action="reallyDelete.php">
    <input type="hidden" name="id" value="$id">
    <input type="submit" name="reallydelete" value="Confirm Delete" />
    <input type="button" name="cancel" value="cancel"
    onClick="location.href='addProfile.php'" /></a>
    </p></form></div>
    HERE;
    // close else

    ?>

and after you confirm the deletion, you are then taken to confirm page: "reallyDelete.php". This is the page I am having trouble with. For some reason, my variable does not display the contents of the row/keyword name.

My DB only has 2 columns in it: KeyID and Keyword_Name

here is the delete confirmation page. How could I pass the $id to the db to delete the keyword/record.

  <?php
      include 'db.php';

  $id = $_POST[id];
  $sql = "SELECT * FROM addKeywordTable WHERE Keyword_Name = '$id'";

  while ($row = mysqli_fetch_array($result)) {
  $id = $row['Keyword_Name'];
       } // end while loop

  print "<p> $row has been permanently deleted.</p>";


  $sql="DELETE FROM addKeywordTable WHERE Keyword_Name = '$id'";
  echo "<meta http-equiv='Refresh' content='2; URL=addKeyword.php'>";
  ?>

Any help with this would be great.Below is a screenshot of my sql table for addKeywordTable

Answer 1

In your deleteKey.php you may have an error:

require 'db.php';
$sel_key = $_POST[sel_key];

//SQL statement to select information
$sql = "SELECT * FROM addKeywordTable WHERE keyID = $sel_key";

Should that second line read $sel_key = $_POST['sel_key']; instead?

This would cause the record to never be selected in the query that follows.

Answer 2

I saw is that you never execute the queries in your file deleteKey.php and reallyDelete.php (maybe you didn't want put the full code).

Regards!