[SOLVED] XML > MySQL?

[alexgeek]

I've learnt how to easily handle XML with PHP now.
So which would be faster, a blog driven by parsing XML or querying a database?
I'm pretty sure it's the XML one right?

[Stuart]

That depends on how big you're expecting your blog to get. If you expect it to be huge, I'd go with the XML since it can store more data. However, MySQL is faster. Tough decision! Speed vs. size...

[Rakuli]

I would say MySQL by far!

XML is working with files -- basically treated as text by PHP... MySQL is many times faster than PHP.. So adding the need for PHP to work with XML files would further slow things down..

I wouldn't depart from convention in this case because convention has it right -- use a database

[Stuart]

Yeah, good point. Since it's a blog, text is all he needs to store. But when you add more data, XML becomes slow. However, a MySQL database is hard to manage when you put a lot of data into it, unless you have really good shell software

[alexgeek]

Cheers Luke
Two questions though.
1.) What are the best uses for XML storage?

2.) This is my XML:

HTML: Select all

<?xml version="1.0" encoding="utf-8"?>
<numbers>
    <no>1</no>
    <no>2</no>
    <no>3</no>
</numbers>

And my PHP parsing:

PHP: Select all

define('XML', 'numbers.xml');
$xml = new SimpleXMLElement(XML, NULL, true);

for($i = 4; $i < 200; $i++) {
$xml->addChild('no', $i);
}

foreach($xml as $n) {
echo $n.'<br';
} 

I would expect this to list 1 to 200(abouts) seperated by <br>s but it just print: 1
Without the addChild() loop, it list 1-3.
What am i doing wrong?

[alexgeek]

Originally Posted by swagner

. But when you add more data, XML becomes slow.

Obviously but XML can handle larger data better than MySQL.

[Stuart]

Yes, I know. That's why I originally suggested XML. Luke mentioned that MySQL is faster, and that is also true. So, it really depends...

[alexgeek]

how many times did you just contradict yourself? o_0
"a string like this long do do do doododododododododoododododododododoodo
times about 50 times would go into mysql and 500 times this length into XML"
Agree?

[Stuart]

Yes, XML is better for storage, but MySQL is faster! Read my first post!

[Rakuli]

Yeah, good point. Since it's a blog, text is all he needs to store. But when you add more data, XML becomes slow. However, a MySQL database is hard to manage when you put a lot of data into it, unless you have really good shell software

Relational databases are as good as their design.. If you don't plan your database it will fall apart when data is increased. A well designed database is easy to manage and can contain arbitrary amounts of data. I would never even consider using files over a database if a database was available.


@Alex
You need to rewrite your code a little

PHP: Select all

define('XML', 'numbers.xml');

$xml = new SimpleXMLElement(XML, NULL, true);

$numbers = $xml->addChild('numbers');

for($i = 4; $i < 200; $i++) {

$numbers->addChild('no', $i);

}

foreach($numbers as $n) {echo $n.'<br';} 

You need to add the whle structure -- the way you were doing it, it is just adding <no> elements to the root structure and not withing <numbers>

[alexgeek]

Thanks Luke but that just outputs "4".

[alexgeek]

It generates this XML:

HTML: Select all

<?xml version="1.0" encoding="utf-8"?>
<numbers>
  <no>1</no>
  <no>2</no>
  <no>3</no>
  <numbers>
    <no>4</no>
    <no>5</no>
    <no>6</no>
    <no>7</no>
    <no>8</no>
    <no>x</no> 
....

edit!

This code generates the right XML but I still can't get it to loop through.

PHP: Select all

<?php 

define('XML', 'numbers.xml');

$xml = new SimpleXMLElement(XML, NULL, true);

$numbers = $xml;

for($i = 4; $i < 200; $i++) {

$numbers->addChild('no', $i);

}

foreach($xml as $n) {echo $n.'<br';} 
$xml->asXML(XML);
 ?>

[Rakuli]

Okay I didn't so that quite right I don't think..

PHP: Select all

define('XML', 'numbers.xml');

$xml = new SimpleXMLElement(XML, NULL, true);

$numbers = $xml->children();

$numbers = $numbers[0]

for($i = 4; $i < 200; $i++) {

$numbers->addChild('no', $i);

}

foreach($numbers as $n) {echo $n.'<br';} 

I forgot to grab the reference to numbers -- I was adding one previously... This meant there were two lots of numbers.

[alexgeek]

Thanks Luke, that was almost right just needed to alter the $numbers variable.
I think you were referencing to a lower level when you were actually on it.
$xml when defined holds <numbers>, and I think you were trying to access numbers like: $xml->numbers - which doesn't exist.

Anyway this code works perfectly. Thanks (thread solved)

PHP: Select all

define('XML', 'numbers.xml');

$xml = new SimpleXMLElement(XML, NULL, true);

$numbers = $xml;

$numbers = $numbers[0];

for($i = 4; $i < 200; $i++) {

$numbers->addChild('no', $i);

}

foreach($numbers as $n) {echo $n.'<br>'; }
$xml->asXML(XML) 

HTML: Select all

<?xml version="1.0" encoding="utf-8"?>
<numbers>
  <no>1</no>
  <no>2</no>
  <no>3</no>
  <no>4</no>
  <no>X</no>
</numbers>

P.S. I'm going to create a settings API, allowing an easy way to set, retrieve and edit settings that get stored in XML file.