How to set an alias to a fields on a db_select?
Use addField(). Here's an example:

$query = db_select('super_long_table', 'slt');
$query-&gt;addField('slt', 'mys_super_long_field', 'mslf');


Arguments passed to addField() are:


Table alias
Field - your long field name will be here
Alias - your short field alias will be here


Read more about it here.