You can use true or false. Assuming your column's lookup name is #read (seems to be from your examples), then #read:true will find all books that have something in the column, and #read:false will find all books that have nothing in the column.
The { and } characters are used in templates, not in searches. EDIT: But perhaps you know this, given the "don't worry" comment.
Last edited by chaley; 11-04-2014 at 10:01 AM.
|