[EP-tech] Searching in EP 3.2: finding results where a field in empty

[Ian Stuart]

I'm trying to create a search where field A has a value and field B is 
empty (eg creator_name_family = 'Bloggs' and creator_id = '')

How?

   $searchexp->add_field( $dso->get_field("creator_id"),  '' );

doesn't work

Thankee
(EP 3.2.2, if that helps)
-- 

Ian Stuart.
Developer: ORI, RJ-Broker, and OpenDepot.org
Bibliographics and Multimedia Service Delivery team,
EDINA,
The University of Edinburgh.

http://edina.ac.uk/

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