[Qgis-user] Filtering NULL values from WFS

[Reetz, Michael (NLPVW)]

Hello group,

I've added a WFS-layer to a project try to define filters on different attributes. It seems not to be possible to filter for NULL values.

Example:

  *   1932 records in total
  *   376 records with a value in a date attribute
  *   20 records with 2005-12-31 as value

If I set the filter to "end_date" = '2005-12-31' the result is 20 records.
If I set the filter to "end_date" != '2005-12-31' the result is 356 records. So only records that have an end date are recognized. Record with NULL as end date are ignored.

Filtering in the attribute table with "is_empty_or_null" works but only for selection.

Is this "normal" behaviour with WFS layers or is there a way to define a filter string that work for all records?

QGIS-Version is 3.40.4-Bratislava


Best regards

Michael

*****************************************
Michael Reetz
Datenbanken und Anwendungsentwicklung
Nationalpark-Verwaltung Niedersächsisches Wattenmeer
Virchowstr. 1 | 26382 Wilhelmshaven
Tel.: +49 (0) 4421 911 291
e-mail: michael.reetz at nlpvw.niedersachsen.de<mailto:michael.reetz at nlpv-wattenmeer.niedersachsen.de>
Web: https://www.<https://www./>nationalpark-wattenmeer.de
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