The print_r function in PHP lets you "print raw" the contents of a variable - great for debugging and far better that print which - if you pass it an array helpfully says Array

Embed your print_r into <pre> to </pre> tags ... so that you get a good display on your browser ... otherwise you'll end up with the spaces removed and a mess. Here's an example - showing the global $_SERVER array, and also the contents of a table that's been brought back to an array of arrays:

<pre><?php
# Show server variables
print_r($_SERVER);
print ("----------------------------\n");
mysql_connect("127.0.0.1","wellho","xxxxxx");
mysql_select_db("wellho");
$rr = mysql_query("select * from recent limit 15");
print_r($rr);
print ("----------------------------\n");
$stuff = array();
while ($nextrow = mysql_fetch_assoc($rr)) {
  array_push($stuff,$nextrow); }
print_r ($stuff);
?></pre>

Select here to see what you get when you run that code. Note how the mysql_query call just returns a resource handle, and you then have to use something like mysql_fetch_assoc to get the actual data back.


(written 2009-10-01, updated 2010-05-16)

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  [2561] The future of MySQL - (2010-01-03)
  [2447] MySQL stored procedures / their use on the web from PHP - (2009-10-10)
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  [666] Database design - get it right from first principles - (2006-04-02)
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  [572] Giving the researcher power over database analysis - (2006-01-22)
  [515] MySQL - an FAQ - (2005-12-03)
  [104] mysql_connect or mysql_pconnect in PHP? - (2004-10-30)

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Melksham Hotel Rooms - pictures
Serialization - storing and reloading objects
Abstract classes, Interfaces, PHP and Java
Controlling, supressing, enabling PHP error messages
Using print_r in PHP to explore mysql database requests
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Not just a PHP program - a good web application
Tcl scripts / processes on a web server via CGI
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