PDO Database Class

A database class for PHP-MySQL which uses the PDO extension.

To-do

1. PSR-0 / PSR-1 coding standards

2. Use namespaces

3. Dependency Injection / Testability

If you have any questions go to : http://indieteq.com/index/readmore/how-to-prevent-sql-injection-in-php

To use the class

1. Edit the database settings in the settings.ini.php

Note if PDO is loading slow change localhost to -> 127.0.0.1 !

[SQL]
host = 127.0.0.1
user = root
password = 
dbname = yourdatabase

2. Require the class in your project

<?php
require("Db.class.php");

3. Create the instance

<?php
// The instance
$db = new Db();

4. Logs - Modify the read/write rights of the root folder

Everytime an exception is thrown by the database class a log file gets created or modified. These logs are stored in the logs directory. Which means the database class needs write access for the logs folder. If the files are on a webserver you'll have to modify the rights of the root folder otherwise you'll get a "Permission denied" error.

The log file is a simple plain text file with the current date('year-month-day') as filename.

Examples

Below some examples of the basic functions of the database class. I've included a SQL dump so you can easily test the database class functions.

The persons table

id	firstname	lastname	sex	age
1	John	Doe	M	19
2	Bob	Black	M	41
3	Zoe	Chan	F	20
4	Kona	Khan	M	14
5	Kader	Khan	M	56

Fetching everything from the table

<?php
// Fetch whole table
$persons = $db->query("SELECT * FROM persons");

Fetching with Bindings (ANTI-SQL-INJECTION):

Binding parameters is the best way to prevent SQL injection. The class prepares your SQL query and binds the parameters afterwards.

There are three different ways to bind parameters.

<?php
// 1. Read friendly method  
$db->bind("id","1");
$db->bind("firstname","John");
$person   =  $db->query("SELECT * FROM Persons WHERE firstname = :firstname AND id = :id");

// 2. Bind more parameters
$db->bindMore(array("firstname"=>"John","id"=>"1"));
$person   =  $db->query("SELECT * FROM Persons WHERE firstname = :firstname AND id = :id"));

// 3. Or just give the parameters to the method
$person   =  $db->query("SELECT * FROM Persons WHERE firstname = :firstname AND id = :id",array("firstname"=>"John","id"=>"1"));

More about SQL injection prevention : http://indieteq.com/index/readmore/how-to-prevent-sql-injection-in-php

Fetching Row:

This method always returns only 1 row.

<?php
// Fetch a row
$ages     =  $db->row("SELECT * FROM Persons WHERE  id = :id", array("id"=>"1"));

Result

id	firstname	lastname	sex	age
1	John	Doe	M	19

Fetching Single Value:

This method returns only one single value of a record.

<?php
// Fetch one single value
$db->bind("id","3");
$firstname = $db->single("SELECT firstname FROM Persons WHERE id = :id");

Result

firstname
Zoe

Using the like keyword

<?php
// Using Like 
// Notice the wildcard at the end of the value!!
$like = $db->query("SELECT * FROM Persons WHERE Firstname LIKE :firstname ", array("firstname"=>"sekit%"));

Result

id	firstname	lastname	sex	age
4	Sekito	Khan	M	19

Fetching Column:

<?php
// Fetch a column
$names    =  $db->column("SELECT Firstname FROM Persons");

Result

firstname
John
Bob
Zoe
Kona
Kader

Delete / Update / Insert

When executing the delete, update, or insert statement by using the query method the affected rows will be returned.

<?php

// Delete
$delete   =  $db->query("DELETE FROM Persons WHERE Id = :id", array("id"=>"1"));

// Update
$update   =  $db->query("UPDATE Persons SET firstname = :f WHERE Id = :id", array("f"=>"Jan","id"=>"32"));

// Insert
$insert   =  $db->query("INSERT INTO Persons(Firstname,Age) VALUES(:f,:age)", array("f"=>"Vivek","age"=>"20"));

// Do something with the data 
if($insert > 0 ) {
  return 'Succesfully created a new person !';
}

Method parameters

Every method which executes a query has the optional parameter called bindings.

The row and the query method have a third optional parameter which is the fetch style. The default fetch style is PDO::FETCH_ASSOC which returns an associative array.

Here an example :

<?php
  // Fetch style as third parameter
  $person_num =     $db->row("SELECT * FROM Persons WHERE id = :id", array("id"=>"1"), PDO::FETCH_NUM);

  print_r($person_num);
  // Array ( [0] => 1 [1] => Johny [2] => Doe [3] => M [4] => 19 )
    

More info about the PDO fetchstyle : http://php.net/manual/en/pdostatement.fetch.php

EasyCRUD

The easyCRUD is a class which you can use to easily execute basic SQL operations like(insert, update, select, delete) on your database. It uses the database class I've created to execute the SQL queries.

Actually it's just a little ORM class.

How to use easyCRUD

1. First, create a new class. Then require the easyCRUD class.

2. Extend your class to the base class Crud and add the following fields to the class.

Example class :

<?php
require_once("easyCRUD.class.php");
 
class YourClass  Extends Crud {
 
  # The table you want to perform the database actions on
  protected $table = 'persons';

  # Primary Key of the table
  protected $pk  = 'id';
  
}

EasyCRUD in action.

Creating a new person

<?php
// First we"ll have create the instance of the class
$person = new person();
 
// Create new person
$person->Firstname  = "Kona";
$person->Age        = "20";
$person->Sex        = "F";
$created            = $person->Create();
 
//  Or give the bindings to the constructor
$person  = new person(array("Firstname"=>"Kona","age"=>"20","sex"=>"F"));
$created = $person->Create();
 
// SQL Equivalent
"INSERT INTO persons (Firstname,Age,Sex) VALUES ('Kona','20','F')"

Deleting a person

<?php
// Delete person
$person->Id  = "17";
$deleted     = $person->Delete();
 
// Shorthand method, give id as parameter
$deleted     = $person->Delete(17);
 
// SQL Equivalent
"DELETE FROM persons WHERE Id = 17 LIMIT 1"

Saving person's data

<?php
// Update personal data
$person->Firstname = "John";
$person->Age  = "20";
$person->Sex = "F";
$person->Id  = "4"; 
// Returns affected rows
$saved = $person->Save();
 
//  Or give the bindings to the constructor
$person = new person(array("Firstname"=>"John","age"=>"20","sex"=>"F","Id"=>"4"));
$saved = $person->Save();
 
// SQL Equivalent
"UPDATE persons SET Firstname = 'John',Age = 20, Sex = 'F' WHERE Id= 4"

Finding a person

<?php
// Find person
$person->Id = "1";
$person->find();

echo $person->Firstname;
// Johny
 
// Shorthand method, give id as parameter
$person->find(1); 
 
// SQL Equivalent
"SELECT * FROM persons WHERE Id = 1"

Getting all the persons

<?php
// Finding all person
$persons = $person->all(); 
 
// SQL Equivalent
"SELECT * FROM persons 

Copyright and license

Code released under Beerware