Most of the time the pChart library will be linked to a database in order to retrieve dynamic data. This tutorial will show you how to use the pChart and the pData classes to adapt SQL results into a graph. What is done here with MySQL can be easily reused for any kind of database engine like MS SQL server or Oracle.

First of all, connect to your MySQL database:

 $db = mysql_connect("localhost", "username", "password");
 if ( $db == "" ) { echo " DB Connection error...\r\n"; exit(); }

 mysql_select_db("mydatabase",$db);

This code will connect to the MySQL service running on the same server than the PHP script using username / password credential. We're then setting the current database to mydatabase.


The graph data will be first retrieved using an SQL query that will depends on your SQL scheme. This simple example assume that the data is located in the column 'value' of the 'data' table. We're also assuming that you are already connected with your database $db.

$Requete = "SELECT `value` FROM `data`";
$result  = mysql_query($Requete,$db);
while ($row = mysql_fetch_array($result))
 { $DataSet->AddPoint($row["value"],"Serie1"); }

Of course it will be better to order your data if you have an index column (named 'id' here) :

$Requete = "SELECT `value` FROM `data` ORDER BY `id`";
$result  = mysql_query($Requete,$db);
while ($row = mysql_fetch_array($result))
 { $DataSet->AddPoint($row["value"],"Serie1"); }

You can retrieve many series in a single query :

$Requete = "SELECT `value1`,`value2`,`value3` FROM `data` ORDER BY `id`";
$result  = mysql_query($Requete,$db);
while ($row = mysql_fetch_array($result))
 {
  $DataSet->AddPoint($row["value1"],"Serie1");
  $DataSet->AddPoint($row["value2"],"Serie2");
  $DataSet->AddPoint($row["value3"],"Serie3");
 }

When you've retrieved your data, don't forget to mark all series as graphable :

$DataSet->AddAllSeries();   

Don't forget to set the series descriptions! This descriptions can come from an SQL query or be statically set depending of your database content.

Statically :

$DataSet->SetSerieName("Mydescription","Serie1");

A simple way to deal with SQL should be something like :

$Requete = "SELECT `description` FROM `datadescription` WHERE `serie`='Serie1'";
$result  = mysql_query($Requete,$db);
$row     = mysql_fetch_array($result);
$DataSet->SetSerieName($row["description"],"Serie1");

or a more interesting way :

$Requete = "SELECT `description`,`serie` FROM `datadescription`";
$result  = mysql_query($Requete,$db);
while ($row = mysql_fetch_array($result))
 { $DataSet->SetSerieName($row["description"],$row["serie"]); }

..assuming you have a table named 'datadescription' containing two columns 'serie' and 'description'. The 'serie' column containing the ID of the serie we've used while retrieving data : Serie1, Serie2, Serie3 and the description containing the legend text associated.