Question

I have a php page query mysql database, it will return about 20000 rows. However the browser will take above 20 minutes to present. I have added index on my database and it do used it, the query time in command line is about 1 second for 20000 rows. but in web application, it takes long. is anyone know which causing this problem? and better way to improve it?Below is my php code to retrieve the data:

select * from table where Date between '2010-01-01' and '2010-12-31' 
$result1 = mysql_query($query1) or die('Query failed: ' . mysql_error());

while ($line = mysql_fetch_assoc($result1)) {
    echo "\t\t<tr>\n";
    $Data['Date'] = $line['Date'];
    $Data['Time'] = $line['Time'];
    $Data['Serial_No'] = $line['Serial_No'];
    $Data['Department'] = $line['Department'];
    $Data['Team'] = $line['Team'];

    foreach ($Data as $col_value) {
        echo "\t\t\t<td>$col_value</td>\n";
    };
    echo "\t\t</tr>\n";
}

Answer 1

Try adding an index to your date column.

Also, it’s a good idea to learn about the EXPLAIN command.

As mentioned in the comments above, 1 second is still pretty long for your results.

You might consider putting all your output into a single variable and then echoing the variable once the loop is complete.

Also, browsers wait for tables to be completely formed before showing them, so that will slow your results (at least slow the process of building the results in the browser). A list may work better – or better yet a paged view if possible (as recommended in other answers).