Constantes y variables que interesa conocer de Prestashop

_DB_PREFIX_ <- Prefijo para las consultas a la base datos.
_PS_ROOT_DIR_ <- Directorio de instalación: public_html.

define('_PS_ROOT_DIR_', realpath($currentDir.'/..'));
define('_PS_CLASS_DIR_',            _PS_ROOT_DIR_.'/classes/');
define('_PS_CONTROLLER_DIR_',       _PS_ROOT_DIR_.'/controllers/');
define('_PS_FRONT_CONTROLLER_DIR_', _PS_ROOT_DIR_.'/controllers/front/');
define('_PS_ADMIN_CONTROLLER_DIR_', _PS_ROOT_DIR_.'/controllers/admin/');
define('_PS_OVERRIDE_DIR_', _PS_ROOT_DIR_.'/override/');
define('_PS_TRANSLATIONS_DIR_', _PS_ROOT_DIR_.'/translations/');
define('_PS_DOWNLOAD_DIR_',         _PS_ROOT_DIR_.'/download/');
define('_PS_MAIL_DIR_',             _PS_ROOT_DIR_.'/mails/');
define('_PS_PDF_DIR_', _PS_ROOT_DIR_.'/pdf/');
define('_PS_ALL_THEMES_DIR_',       _PS_ROOT_DIR_.'/themes/');
define('_PS_IMG_DIR_',              _PS_ROOT_DIR_.'/img/');
if (!defined('_PS_MODULE_DIR_'))
define('_PS_MODULE_DIR_',              _PS_ROOT_DIR_.'/modules/');
define('_PS_CAT_IMG_DIR_',          _PS_IMG_DIR_.'c/');
define('_PS_STORE_IMG_DIR_', _PS_IMG_DIR_.'st/');
define('_PS_PROD_IMG_DIR_',         _PS_IMG_DIR_.'p/');
define('_PS_SCENE_IMG_DIR_',        _PS_IMG_DIR_.'scenes/');
define('_PS_SCENE_THUMB_IMG_DIR_',  _PS_IMG_DIR_.'scenes/thumbs/');
define('_PS_MANU_IMG_DIR_',         _PS_IMG_DIR_.'m/');
define('_PS_SHIP_IMG_DIR_',         _PS_IMG_DIR_.'s/');
define('_PS_SUPP_IMG_DIR_',         _PS_IMG_DIR_.'su/');
define('_PS_COL_IMG_DIR_', _PS_IMG_DIR_.'co/');
define('_PS_TMP_IMG_DIR_',          _PS_IMG_DIR_.'tmp/');
define('_PS_UPLOAD_DIR_', _PS_ROOT_DIR_.'/upload/');
define('_PS_TOOL_DIR_', _PS_ROOT_DIR_.'/tools/');
define('_PS_GEOIP_DIR_',            _PS_TOOL_DIR_.'geoip/');
define('_PS_SWIFT_DIR_', _PS_TOOL_DIR_.'swift/');
define('_PS_GENDERS_DIR_',            _PS_IMG_DIR_.'genders/');
define('_PS_FPDF_PATH_',            _PS_TOOL_DIR_.'fpdf/'); // @deprecated will be removed in 1.6
define('_PS_TCPDF_PATH_',            _PS_TOOL_DIR_.'tcpdf/');
define('_PS_TAASC_PATH_',            _PS_TOOL_DIR_.'taasc/');
define('_PS_PEAR_XML_PARSER_PATH_', _PS_TOOL_DIR_.'pear_xml_parser/');
define('_PS_CACHE_DIR_', _PS_ROOT_DIR_.'/cache/');
/* BO THEMES */
if (defined('_PS_ADMIN_DIR_'))
define('_PS_BO_ALL_THEMES_DIR_', _PS_ADMIN_DIR_.'/themes/');

01 $base_dir { root folder of your shop }
02 $base_dir_ssl { root folder of your shop using HTTPS protocol }
03 $content_dir { root folder of your shop depending on the SSL settings }
04 $img_ps_dir { root folder containing images "/img/" }
05 $img_dir { images folder in your current theme directory }
06 $css_dir { css folder inside the current theme folder }
07 $js_dir { JavaScript inside the theme folder }
08 $tpl_dir { theme root folder }
09 $modules_dir { modules root folder }
10 $mail_dir { mail templates root folder }
11 $lang_iso { current language ISO code }
12 $come_from { previous page address [absolute] }
13 $shop_name { your specified shop name }
14 $cart_qties { total number of products in the cart }
15 $cart { shopping cart contents }
16 $currencies { pulls available currencies }
17 $id_currency_cookie { selected currency id [cookie dependent] }
18 $currency { active currency }
19 $cookie { active cookie }
20 $languages { grabs available languages }
21 $logged { checks whether users is logged in }
22 $page_name { current page's name }
23 $customerName { customer name [session dependent] }
24 $priceDisplay { current price display settings [currency dependent] }

Reparar el orden de los productos en categorías en Prestashop 1.4

CREATE TABLE `ps_category_product_new` (
  `id_category` int(10) unsigned NOT NULL,
  `id_product` int(10) unsigned NOT NULL,
  `position` int(10) unsigned NOT NULL default '0',
  UNIQUE KEY `category_product_uniq` (`id_category`,`id_product`),
  UNIQUE KEY `category_product_index` (`id_category`,`id_product`),
  KEY `id_product` (`id_product`),
  KEY `position` (`position`,`id_category`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

INSERT INTO
    `ps_category_product_new`
SELECT
    id_category, id_product, row 
FROM 
(
    SELECT
        id_category, id_product, 
        @row := IF(@base = id_category, @row+1, 1) as row, @base := id_category as b 
    FROM
        (
            SELECT 
                cp.id_category, cp.id_product, pl. name
            FROM
                ps_category_product cp 
            LEFT JOIN
                ps_product_lang pl
            USING
                (id_product) 
            WHERE
                id_lang = 3
            ORDER BY 
                id_category, position
        ) AS s,
        (SELECT @row := 1, @base = 0) AS r
) as t;