Data retrieval problem from MySQL

[younus]

I am running the following query in PHP to retrieve data from MySQL database. It works fine when I give id range less than 595 or so (e.g., $low=105, $high=700). But if i increase this number, it results in "Page not found" error or simply a blank page. Can somebody please tell me why it's happening and how can I improve the query etc.? (Note: there are several thousand rows in the database. $curr_book and $new_book are arrrays containg an average of 5 names of books.) Thanks for your help.

$query = mysql_query("select id, datetime, curr_book, new_book from minitest where (id > '$low' && id < '$high')");


if ($query){
echo "
<table border=1>
	<tr>
		<td>No.</td>
		<td>Date/Time</td>
		<td>Current Books</td>
		<td>New Books</td>
	</tr>";


$numOfRows = mysql_num_rows ($query);
  for ($i = 0; $i < $numOfRows; $i++){
	$id = mysql_result ($query, $i, "id");
	$datetime = mysql_result ($query, $i, "datetime");
	$curr_book = mysql_result ($query, $i, "curr_book");
	$new_book = mysql_result ($query, $i, "new_book");


echo "<tr>
		<td>$id</td>
		<td>$datetime</td>
		<td>";

if ($curr_book != "") {
	$curr_book = unserialize( $curr_book);

$currentbooks = implode($curr_book, ", ");
	echo "$currentbooks";
}
else {
	echo "&#151;";
	}

echo "</td><td>";

if ($new_book != "") {
	$new_book = unserialize( $new_book);
$newbooks = implode($new_book, ", ");
	echo "$newbooks";
	}
else {
	echo "&#151;";
	}

echo "</td></tr>";
		}// end for loop

echo "</table>";

}// end if $query

[m_tt]

You could try running a query like

SELECT `id`,`datetime`,`curr_book`,`new_book` FROM minitest WHERE id BETWEEN '" . $low . "' AND '" . $high . "'

but I don't know if that will help 🙁

[m_tt]

Try this, I cleaned it up a bit so you could learn easier methods of looping query results. Let me know if you have any questions 🙂

$output = '';

$qwery	= mysql_query("SELECT `id`,`datetime`,`curr_book`,`new_book` FROM minitest WHERE id BETWEEN '" . $low . "' AND '" . $high . "'")or die(mysql_error());
	if (mysql_nun_rows($query) > 0)	{
	//	Results Found
		//	Add Your Table to the Output
		$output .= '
			<table border="1">
				<th>
					<td>No.</td>
					<td>Date/Time</td>
					<td>Current Book</td>
					<td>New Books</td>
				</th>
				';

	//	Loop the Query Results
	while(list($id,$datetime,$curr_book,$new_book) = mysql_fetch_row($qwery))	{
		//	Add Results to your Output table
		$output .= '
			<tr>
				<td>' . $id . '</td>
				<td>' . $datetime . '</td>
				<td>
			';

		if ($curr_book != "")	{
			$curr_book = unserialize($curr_book);
			$currentbooks = implode($curr_book, ", ");

			$output .= $currentbooks;
		} else {
			$output .= "&#151;";
		}

		$output .= '</td><td>';

		if ($new_book != "")	{
			$new_book = unserialize($new_book);
			$newbooks = implode($new_book, ", ");

			$output .= $newbooks;
		} else {
			$output .= "&#151;";
		}

		$output .= '</td></tr>';

	}	//	End Loop

	$output .= '</table>';

	//	Echo all the output we just generated:
	echo $output;
} else {
//	No Results
	echo "No Query Results!";
}