Please correct me if I'm wrong. It seems that it simply needs to be

$query->fieldCondition('field_name');

and all nodes with an empty field_name field seem get excluded o_O

Please correct me if I'm wrong. It seems that it simply needs to be

$query->fieldCondition('field_name');

to exclude all nodes with an empty field_name field o_O

Tested in Drupal version >= 7.43.

Please correct me if I'm wrong. It seems that it simply needs to be

$query->fieldCondition('field_name');

and all nodes with an empty field_name field seem get excluded.

Please correct me if I'm wrong. It seems that it simply needs to be

$query->fieldCondition('field_name');

and all nodes with an empty field_name field seem get excluded o_O