Moazzam’s Ramblings

127.0.0.1         example.com
::1               example.com

<?php
/** 
* This function will attempt to make a persistent connection to MySQL or die() with a message
* It takes 3 parameters 
*  - hostname or IP to connect to
*  - username 
*  - password (assuming a password is required)
*
* The values I used are the ones that will work by default (unless your installation was different)
* You MUST make sure that the database server is running and you have the right username and 
* password for this to work (but that's obvious)
*/
mysql_pconnect('localhost', 'root', '') or die('Could not connect to the database server');
 
/**
* Now that we are connected and logged in, we select the database we want to use
* And, we kill the script if there is a problem selecting the database.
*
* If this function call fails, that generally means you dont have access to the database.
* Go back to MySQL administration and make sure your username has proper permissions
*/
mysql_select_db('database_name') or die('Could not select the DB');

<?php
 
// ... connect to the MySQL server and select the DB ....
 
/**
* You will need to learn SQL to communicate with MySQL. I won't get into SQL here because that's a whole another tutorial
* I put this query in a variable in case I need to print it out later when debugging. I find it easier to debug with this even  
* in IDEs when stepping through the code
*/ 
$sql = ' 
  CREATE TABLE contacts (
    id int AUTO_INCREMENT,
    first_name varchar(255),
    last_name varchar(255),
    email varchar(255),
    primary key (id)
  )
';
 
/**
* mysql_query() is the function you pass your queries to, so they can be run on MySQL server.
* 
* If  your query contains an error, then mysql_error() will get you that error.
*/
mysql_query($sql) or die('Error occurred:'.mysql_error());

<?php
// ... connect to the MySQL server and select the DB ....
 
/**
* This is what insert statements look like for MySQL
*/
 
 
$sql ="INSERT INTO contacts(
    first_name, 
    last_name, 
    email
  ) VALUES(
      '".mysql_real_escape_string('John')."', 
      '".mysql_real_escape_string('Lango')."', 
      '".mysql_real_escape_string('john@example.com')."'
  )";
 
/**
* As you may have realized, the function you will be using the most is mysql_query()
* You perform all your database operations with it. 
*
* You will perform update and delete this way too. If you need help with the queries for those
* let me know. If enough people request it, I will write another article for it or modify this one 
* to include it. 
* 
* You will also notice I used mysql_real_escape_string() above in the SQL query.
* This function escapes certain special characters in the values you want to insert so
* people don't hijack your database :). And, your script won't break when someone
* uses a single quote in their first name.
*/
mysql_query($sql) or die('insert failed');

<?php
/** Write query */
$sql = 'select * from contacts';
/** Run it */
$result = mysql_query($sql) or die('Select query failed');
/** 
* Fetch the results 
* When you fetch the results, you will see that here $row has your table field names as keys 
*/
while ($row = mysql_fetch_assoc($result)) {
   print "First Name: {$row['first_name']} <BR>\nLast Name:{$row['last_name']} <br>\n Email: {$row['email']} <p>\n\n";
}

<?php
 
/**
* You will need to save the resource returned by mysql_pconnect() to a variable
*/
$conn = mysql_pconnect('localhost', 'root', '');
// ... select the DB .. run some queries, etc ...
/** 
* And, this is the function call to close the connection. It takes the resource $conn 
* as a parameter (so it knows which connection it's closing)
*/
mysql_close($conn);