Prev - Next link tutorial.

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July 28th, 2002, 01:18 AM

Darth Evad

Join Date: Apr 2007

Posts: 4

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Prev - Next link tutorial.

I checked out a couple of these tutorials and decided to go with the one codewalker has.
When I use it I get an Undefined index: count in line...
Also, it won't show the first record of each page. I'm using 6 records per page and it shows 45 - 41 (ORDER BY refnum DESC) when it should show 46 - 41.
Any suggestions.

July 28th, 2002, 01:35 AM

EvilivE

Join Date: Apr 2007

Location: Milwaukee, WI USA

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RE: Prev - Next link tutorial.

Your talking about this:

php Code:

Original - php Code
$query = "SELECT count(*) as count FROM table"; $result = mysql_query($query); $row = mysql_fetch_array($result); $numrows = $row['count'];

$query = "SELECT count(*) as count FROM table"; 
$result = mysql_query($query);
$row = mysql_fetch_array($result);
$numrows = $row['count'];

Try changing the index count to total. So it looks like this:

php Code:

Original - php Code
$query = "SELECT count(*) as total FROM table"; $result = mysql_query($query); $row = mysql_fetch_array($result); $numrows = $row['total'];

$query = "SELECT count(*) as total FROM table"; 
$result = mysql_query($query);
$row = mysql_fetch_array($result);
$numrows = $row['total'];

HTH

July 28th, 2002, 01:47 AM

Darth Evad

Join Date: Apr 2007

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RE: Prev - Next link tutorial.

Still the same. I guess I should provide some code incase it's a problem elsewhere.

php Code:

Original - php Code

 
<?
 
$host = 'localhost';
$user = 'evad';
$password = 'evad';
$db = 'darth';
 
if(!isset($start))
{
    $start=0;
}
 
$link_id = mysql_connect($host, $user, $password);
mysql_select_db($db);
$query = ("SELECT * FROM dave ORDER BY refnum DESC LIMIT " . $start . ", 6");
$result = mysql_query($query);
$query = ("SELECT count(*) as total FROM apartment ORDER BY refnum DESC");
$row = mysql_fetch_array($result);
$numrows = $row['total']; //THIS IS WHERE THE UNDEFINED INDEX IS
 
while ($query_data = mysql_fetch_row($result))
{
    echo ("<table><tr><td rowspan=11><a href='images/example.jpg' target='any-window'><img src='images/example.jpg' alt='Your home in color' width='175' height='131' align='left'></a></td></tr><tr><td width=135>Name - </td><td>$query_data[0]</td></tr><tr><td>Phone number - </td><td>$query_data[1]</td></tr><tr><td>E-mail - <td><a class=mail href=mailto:$query_data[2]>$query_data[2]</a></td></tr><tr><td>Bedrooms - </td><td>$query_data[3]</td></tr><tr><td>Bathrooms - </td><td>$query_data[4]</td></tr><tr><td>Square feet - </td><td>$query_data[5]</td></tr><tr><td>Description - </td><td>$query_data[6]</td></tr><tr><td>Date submitted - </td><td>$query_data[7]</td></tr><tr><td>Reference number - </td><td>$query_data[8]</td></tr><tr><td><form><input type=submit name='approve' value='Approved'></form></td></tr></table><hr>");
}
 
if($start > 0) 
{
   echo "<div align="left"><a href="" . $PHP_SELF . "?start=" . ($start - 6) . 
        "">Previous Page</a></div>";
}
if($numrows > ($start + 6)) 
{
   echo "<div align="right"><a href="" . $PHP_SELF . "?start=" . ($start + 6) . 
        "">Next Page</a></div>";
}
 
?>

July 28th, 2002, 02:08 AM

EvilivE

Join Date: Apr 2007

Location: Milwaukee, WI USA

Posts: 291

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RE: Prev - Next link tutorial.

OK, let me give this a shot.

First thing: There is no need to place parens, (), around you assignments to $query.
Second: Parens are not required for echo, take those out.
Third: to be consistent with the tutorial your echo statment is in the wrong place (and this is where your problem starts).

//You assigned $query to this string, take out parens
$query = ("SELECT * FROM dave ORDER BY refnum DESC LIMIT " . $start . ", 6");

// this is where you actually query the db
$result = mysql_query($query);

// then you assigned $query to this other string, take parens out
$query = ("SELECT count(*) as total FROM apartment ORDER BY refnum DESC");

// here you assign $row to the result set of your _FIRST_ query
$row = mysql_fetch_array($result);

// now your trying to use an index value total but this index value is in your second query that you never executed
$numrows = $row['total'];

I hope that makes a little sense.

July 28th, 2002, 02:44 AM

Anonymous

Registered User

Codewalkers God 35th Plane (22000 - 22499 posts)

Join Date: Apr 2007

Posts: 22,309

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RE: Prev - Next link tutorial.

No. ;)
See my sig. :p

I understand what I've got now.
I don't understand why I am missing every 6th record starting with number 1.
I also don't understand why I get the undefined index.

Thanks though.

July 28th, 2002, 03:52 AM

EvilivE

Join Date: Apr 2007

Location: Milwaukee, WI USA

Posts: 291

Time spent in forums: < 1 sec
Reputation Power: 2

RE: Prev - Next link tutorial.

Lets work on one problem at a time, the index thing.
It is more important to understand why it is happening as opposed to me giving you the code to fix it, feed a person for life mentality.

This is the logic:
a) build a query string
b) execute query
c) create an array with data
d) do something with data

// lets call this, ummmmm, FIRST_QUERY. now you have part "a" done
$query = ("SELECT * FROM dave ORDER BY refnum DESC LIMIT " . $start . ", 6");

// this is part "b" for FIRST_QUERY
$result = mysql_query($query);

// this is part "a" for SECOND_QUERY
$query = ("SELECT count(*) as total FROM apartment ORDER BY refnum DESC");

// this is part "c" for FIRST_QUERY
$row = mysql_fetch_array($result);

// this is part "d" of SECOND_QUERY
$numrows = $row['total'];

// this is again part "c" for FIRST_QUERY
while ($query_data = mysql_fetch_row($result))

Something is missing, right?

July 28th, 2002, 04:15 AM

EvilivE

Join Date: Apr 2007

Location: Milwaukee, WI USA

Posts: 291

Time spent in forums: < 1 sec
Reputation Power: 2

RE: Prev - Next link tutorial.

Try this:

php Code:

Original - php Code

<?
// THIS INFO SHOULD NEVER BE HERE!!!!!!!!!!!!!!!!!!!!!!!
// PLACE IT IN A DIRECTORY OUTSIDE YOUR SERVERS DOCUMENT ROOT !!!!!!!!!!!!!

$host = 'localhost';
$user = 'evad';
$password = 'evad';
$db = 'darth';

if(!isset($start))
{
    $start=0;
}

// connect to mysql and select a db
$link_id = mysql_connect($host, $user, $password);
mysql_select_db($db);

$query  = "SELECT * FROM dave ORDER BY refnum DESC LIMIT " . $start . ", 6";
$result = mysql_query($query);
while ($query_data = mysql_fetch_row($result)){ // you could use mysql_fetch_array() here, then you could access the indicies by "name"
  echo "<table>
          <tr>
            <td rowspan=11><a href='images/example.jpg' target='any-window'><img src='images/example.jpg' alt='Your home in color' width='175' height='131' align='left'></a></td>
          </tr>
          <tr>
            <td width=135>Name - </td>
            <td>".$query_data[0]."</td>
          </tr>
          <tr>
            <td>Phone number - </td>
            <td>".$query_data[1]."</td>
          </tr>
          <tr>
            <td>E-mail - </td>
            <td><a class=mail href=mailto:".$query_data[2].">".$query_data[2]."</a></td>
          </tr>
          <tr>
            <td>Bedrooms - </td>
            <td>".$query_data[3]."</td>
          </tr>
          <tr>
            <td>Bathrooms - </td>
            <td>".$query_data[4]."</td>
          </tr>
          <tr>
            <td>Square feet - </td>
            <td>".$query_data[5]."</td>
          </tr>
          <tr>
            <td>Description - </td>
            <td>".$query_data[6]."</td>
          </tr>
          <tr>
            <td>Date submitted - </td>
            <td>".$query_data[7]."</td>
          </tr>
          <tr>
            <td>Reference number - </td>
            <td>".$query_data[8]."</td>
          </tr>
          <tr>
            <td><form><input type=submit name='approve' value='Approved'></form></td>
          </tr>
        </table>
        <hr>";
}

$query   = "SELECT count(*) as total FROM apartment ORDER BY refnum DESC";
$result  = mysql_query($query);
$row     = mysql_fetch_array(result);
$numrows = $row['total'];

if($start > 0) 
{
   echo "<div align="left"><a href="" . $PHP_SELF . "?start=" . ($start - 6) . 
        "">Previous Page</a></div>";
}
if($numrows > ($start + 6)) 
{
   echo "<div align="right"><a href="" . $PHP_SELF . "?start=" . ($start + 6) . 
        "">Next Page</a></div>";
}

 
<?
// THIS INFO SHOULD NEVER BE HERE!!!!!!!!!!!!!!!!!!!!!!!
// PLACE IT IN A DIRECTORY OUTSIDE YOUR SERVERS DOCUMENT ROOT !!!!!!!!!!!!!
 
$host = 'localhost';
$user = 'evad';
$password = 'evad';
$db = 'darth';
 
if(!isset($start))
{
    $start=0;
}
 
// connect to mysql and select a db
$link_id = mysql_connect($host, $user, $password);
mysql_select_db($db);
 
 
$query  = "SELECT * FROM dave ORDER BY refnum DESC LIMIT " . $start . ", 6";
$result = mysql_query($query);
while ($query_data = mysql_fetch_row($result)){ // you could use mysql_fetch_array() here, then you could access the indicies by "name"
  echo "<table>
          <tr>
            <td rowspan=11><a href='images/example.jpg' target='any-window'><img src='images/example.jpg' alt='Your home in color' width='175' height='131' align='left'></a></td>
          </tr>
          <tr>
            <td width=135>Name - </td>
            <td>".$query_data[0]."</td>
          </tr>
          <tr>
            <td>Phone number - </td>
            <td>".$query_data[1]."</td>
          </tr>
          <tr>
            <td>E-mail - </td>
            <td><a class=mail href=mailto:".$query_data[2].">".$query_data[2]."</a></td>
          </tr>
          <tr>
            <td>Bedrooms - </td>
            <td>".$query_data[3]."</td>
          </tr>
          <tr>
            <td>Bathrooms - </td>
            <td>".$query_data[4]."</td>
          </tr>
          <tr>
            <td>Square feet - </td>
            <td>".$query_data[5]."</td>
          </tr>
          <tr>
            <td>Description - </td>
            <td>".$query_data[6]."</td>
          </tr>
          <tr>
            <td>Date submitted - </td>
            <td>".$query_data[7]."</td>
          </tr>
          <tr>
            <td>Reference number - </td>
            <td>".$query_data[8]."</td>
          </tr>
          <tr>
            <td><form><input type=submit name='approve' value='Approved'></form></td>
          </tr>
        </table>
        <hr>";
}
 
$query   = "SELECT count(*) as total FROM apartment ORDER BY refnum DESC";
$result  = mysql_query($query);
$row     = mysql_fetch_array(result);
$numrows = $row['total'];
 
if($start > 0) 
{
   echo "<div align="left"><a href="" . $PHP_SELF . "?start=" . ($start - 6) . 
        "">Previous Page</a></div>";
}
if($numrows > ($start + 6)) 
{
   echo "<div align="right"><a href="" . $PHP_SELF . "?start=" . ($start + 6) . 
        "">Next Page</a></div>";
}
 
?>

It should get you started, _study_ it.