Query Failing....Again

San_John

Once again I bring my insignificant problems before the PHP gurus--only as a last resort of course.

Ok, so I have the following code:

<?php
#Choosing the correct database/establishing connection
$connection = mysql_connect("localhost", "XXXXX", "XXXX") or die("Death!");
$pickdatabase = mysql_select_db("ods1", $connection)
	   		  or die("Database Connection Problem!");
$_GET['delid'];
$_GET['dbtable'];
$_GET['idfield'];
$_GET['origin'];

$deleteform="<form align=\"Center\" action=\"$PHP_SELF\" method=\"post\">";
$deleteform.="<p>Are You Sure You Want To Delete This Record?</p>";
$deleteform.="<a href=\"$origin\">Back</a>";
$deleteform.="<input type=\"submit\" name=\"cdelete\" value=\"Confirm Delete\"></input>";
$deleteform.="</form>";


if($cdelete){
$delquery = "delete from $dbtable where $idfield='$delid'";
$runit=mysql_query($delquery, $connection) or die("Query failed");
echo("Record Deleted");
echo($deleteform);
}
else{

echo($deleteform);
}
?>

What I'm trying to do is create a generic delete function that can delete any field given to it from various other pages. Everything works fine except that when you click on the Confirm Delete Button in the form above, it says Query Failed. I don't get it. I can tell from the url that all the info is being sent correctly from the other pages.

YappyDog

I suspect if you printed out your query just before you executed it you'd see you don't have anything in your variables.

Instead of this:

$GET['delid'];
$GET['dbtable'];
$GET['idfield'];
$GET['origin'];

I think you want:

$delid = $GET['delid'];
$dbtable = $GET['dbtable'];
$idfield = $GET['idfield'];
$origin = $GET['origin'];

You also probably need to add:

$cdelete = $_POST["cdelete"];

San_John

You were somewhat correct. However, when I do it your way and then print out all the variables they come out just fine, but the query still fails.

YappyDog

Did you print out the contents of $delquery before you ran it?

What does it contain?

If it looks okay, can you run this query interactively and see what error message you get?

San_John

excellent idea, I should have thought of trying that

delete from where = ''

This is what gets printed out when I print the query before running it. Could there be something wrong with the syntax of the query?

$delquery = "delete from $dbtable where $idfield = '$delid'";

Am I supposed to enclose variables in quotes or something? I'll give it a shot

San_John

I wonder if this is an issue of scope with the variables

I tried this:

if($cdelete){
$delid = $_GET['delid']; 
$dbtable = $_GET['dbtable']; 
$idfield = $_GET['idfield']; 
$origin = $_GET['origin'];
echo($delid.$dbtable.$idfield.$origin);

$delquery = "delete from $dbtable where $idfield = $delid";
echo($delquery);
$runit=mysql_query($delquery, $connection) or die("Query failed");
echo("Record Deleted");
echo($deleteform);
}

note the debug echo statement:

echo($delid.$dbtable.$idfield.$origin);

When that statement was outside the

if($cdelete){

It printed out the variables correctly. Now, as it stands above, nothing gets printed.

YappyDog

Looks like you'll need to include your variables as hidden fields within your form so that you get them to use in your query.

San_John

$deleteform.="<input type=\"hidden\" name=\"$delid\"></input>";

Like this or like this:

$deleteform.="<input type=\"hidden\" name=\"delid\"></input>";

I tried both ways. Same result. When I print out the query I get delete from where ='' Why the " ? What do you think that means?

YappyDog

You need to give the hidden fields a value.......

deleteform.="<input type=\"hidden\" name=delid value=\"$delid\"></input>";

San_John

Ok, did it. Same results though. WHere in the code should the

$delid=$_GET['delid'];

be though?

YappyDog

Now that the variables are coming from your form (with method=post), you'll need to use the $_POST array to retrieve the values...

You'll want to put them inside your if statement.

$delid=$_POST['delid'];

Leave the $_GET versions outside the if statement so you can populate your hidden fields.

San_John

It worked. Thank you so much Yappydog, oh great guru of PHP.

It all makes sense now, but what's confusing is that I had it working without doing all of that stuff. The difference was that I wasn't using any forms, I just deleted the record outright. It was when I added the form that problems crept in.

Appreciate it.