php - mysql custom global defined variable -

in database design, tend store variable meant acting role or type smallint. example :

create table `house` (    `id` int(11) not null auto_increment,    `type` smallint(11) not null, 

and in php,

define('house_small_type', '0'); define('house_medium_type', '1'); 

so in php, in select queries :

$this->db->query("select * house                       type=?;", house_small_type); 

my questions :

1. in php part, there better way ?
2. in mysql itself, mysql has global define functionality (like define in php) ?

i want kind of

select * house  type = house_small_type 

in mysql query.
purpose when select in mysql, no way i'm going keep mapping value 0,1,2 real meaning. convineance viewing tables values, without changing structure table , fields.

i suggest using mysql variables:

set house_small_type = 0; set house_medium_type = 1; 

then, in queries may use these variables:

select * house  type = @house_small_type; 

this method defines session variables:

if change session system variable, value remains in effect until session ends or until change variable different value. change not visible other clients.

if want define global mysql variables (available sessions):

set global house_small_type = 0; set global house_medium_type = 1; 

to indicate explicitly variable global variable, precede name global or @@global.. super privilege required set global variables.

documentation:
set statement
using system variables
user-defined variables