mysql_fetch_assoc vs foreach

[asmith]

I've been getting my tabular data from database and printing it on the screen like this :

 

<?php

while ($row = mysql_fetch_assoc($result))
     echo '<tr><td>...';

?>

 

I've noticed in some scripts that the writer have done something like this:

 

<?php

$content = array();
while ($row = mysql_fetch_assoc($result))
    $content[$row['field']] = $value;

foreach ($content as $field => $value)
     echo '<tr><td>...';

?>

 

They get the data and store it in an array, Then use the loop for an array.

At first I thought "well storing in some place else, Then again using a loop for it? That's makes yoru script slower"

 

But when I actually tried the script, It seemed that it is working even faster than mine (The direct echo from looping mysql result)

 

Am I missing something here, Or storing the data in an array then go through the loop is faster? 

 

 

 

[dzelenika]

What amount of data you have to see the difference?

 

It is possible that first script is slower because it is wandering between database reading and writing HTTP response, while second in first step only reads data from database and in second writes it...

[asmith]

Actually it is in pagination, showing about 20 rows per page, In each row about 15 fields are being read.

[rhodesa]

i can't imagine why, for any reason, the second case would be faster. i can see the need for it in certain cases though...wherever you need to know future date before outputting the first row

[waynewex]

The second example is pretty redundant.

 

The first one prints the data straight out whereas the second example assigns the values from each row to an array and the starts ANOTHER loop just to print it out.

[Daniel0]

The second will need more memory.

 

If you need to pass an entire result set to something else you can lazy load it for improved performance. I once wrote an example of that. Try to search the forums for it.