Query/classes/db_util.php

138 lines
2.9 KiB
PHP

<?php
/**
* Query
*
* Free Query Builder / Database Abstraction Layer
*
* @package Query
* @author Timothy J. Warren
* @copyright Copyright (c) 2012 - 2014
* @link https://github.com/aviat4ion/Query
* @license http://philsturgeon.co.uk/code/dbad-license
*/
// --------------------------------------------------------------------------
/**
* Abstract class defining database / table creation methods
*
* @package Query
* @subpackage Drivers
*/
abstract class DB_Util {
/**
* Reference to the current connection object
*/
private $conn;
/**
* Save a reference to the connection object for later use
*
* @param object $conn
*/
public function __construct($conn)
{
$this->conn = $conn;
}
// --------------------------------------------------------------------------
/**
* Enable calling driver methods
*
* @param string $method
* @param array $args
* @return mixed
*/
public function __call($method, $args)
{
return call_user_func_array(array($this->conn, $method), $args);
}
// --------------------------------------------------------------------------
// ! Abstract Methods
// --------------------------------------------------------------------------
/**
* Convienience public function to generate sql for creating a db table
*
* @param string $name
* @param array $fields
* @param array $constraints
* @param array $indexes
*
* @return string
*/
public function create_table($name, $fields, array $constraints=array(), array $indexes=array())
{
$column_array = array();
// Reorganize into an array indexed with column information
// Eg $column_array[$colname] = array(
// 'type' => ...,
// 'constraint' => ...,
// 'index' => ...,
// )
foreach($fields as $colname => $type)
{
$column_array[$colname] = array();
$column_array[$colname]['type'] = ($type !== $colname) ? $type : '';
}
if( ! empty($constraints))
{
foreach($constraints as $col => $const)
{
$column_array[$col]['constraint'] = $const;
}
}
// Join column definitons together
$columns = array();
foreach($column_array as $n => $props)
{
$str = '"'.$n.'"';
$str .= (isset($props['type'])) ? " {$props['type']}" : "";
$str .= (isset($props['constraint'])) ? " {$props['constraint']}" : "";
$columns[] = $str;
}
// Generate the sql for the creation of the table
$sql = 'CREATE TABLE "'.$name.'" (';
$sql .= implode(', ', $columns);
$sql .= ')';
return $sql;
}
/**
* Drop the selected table
*
* @param string $name
* @return string
*/
public function delete_table($name)
{
return 'DROP TABLE "'.$name.'"';
}
/**
* Return an SQL file with the database table structure
*
* @abstract
* @return string
*/
abstract public function backup_structure();
/**
* Return an SQL file with the database data as insert statements
*
* @abstract
* @return string
*/
abstract public function backup_data();
}
// End of db_util.php