php - Column Ambiguous Error in Laravel 4 -

i have query below in laravel 4. in lists, did specified 'units.unit' got column ambiguous error.

$unit = unit::join('bookings','bookings.unit','=','units.unit')->where('bookings.id', '=', $id)->lists('units.unit', 'units.id'); 

sqlstate[23000]: integrity constraint violation: 1052 champ: 'unit' dans field list est ambigu (sql: select unit, units.id units inner join bookings on bookings.unit = units.unit bookings.id = 22)

where goes wrong?

you may try this:

$unit = unit::join('bookings', 'bookings.unit', '=', 'units.unit')             ->where('bookings.id', $id)             ->select(                 'units.id',                 'units.unit',                 'bookings.id bid',                 'bookings.unit bunit'             )             ->lists('units.unit', 'units.id');