EPrints Technical Mailing List Archive

Message: #09207

< Previous (by date) | Next (by date) > | < Previous (in thread) | Next (in thread) > | Messages - Most Recent First | Threads - Most Recent First

[EP-tech] Search filters: negation or searching for "either X or NULL"

CAUTION: This e-mail originated outside the University of Southampton.
--- Begin Message ---
Hi everyone,

I'm having a hard time creating the correct filter for a custom OAI set and I was hoping for some help here.

The set is based on a field which can be either TRUE, FALSE or NULL. It should contain only records where the value is not TRUE (alternatively where it's either FALSE or NULL).

I have not found out how to negate/invert a filter, so I could search for "not TRUE". Neither have I managed to filter for "has value of FALSE or has no value at all".

The snipped below excludes all NULLs, presumably because it treats "NULL" as a string here.

  meta_fields => [ "my_field" ],
  value => "FALSE NULL",
  match => "IN",
  merge => "ANY"

AFAIK, multiple filters are always combined with logical AND. Is there a way to change this to "AND NOT" or "OR"?

I'm sure this is possible somehow and I'll feel quite stupid once someone points it out. :)

Many thanks in advance and best regards
Dennis Müller, B.A.

Universität Mannheim
Digitale Bibliotheksdienste | Schloss Schneckenhof West | 68131 Mannheim

Tel: +49 621 181-3023
- dennis.mueller@uni-mannheim.de (Persönlich)
- alma.ub@uni-mannheim.de (Alma, Primo, Systembibliothekarisches)
- support.ub@uni-mannheim.de (PC-Support)

Web: www.bib.uni-mannheim.de

Attachment: smime.p7s
Description: S/MIME Cryptographic Signature

--- End Message ---