Bug report #5330
Join: Null data handling different for a joint column than for a normal attribute column
|Affected QGIS version:||master||Regression?:||No|
|Operating System:||Easy fix?:||No|
|Pull Request or Patch supplied:||No||Resolution:||fixed/implemented|
|Crashes QGIS or corrupts data:||No||Copied to github as #:||15031|
Using the attached data (data is from GADM, I hope using it here does not violate redissemination rules...):
- Load Bel_adm2.shp
- Load testdata.dbf (this file has data for all features in Bel_adm2 except for 2 - these feature have NULL values in the testdata column of Bel_adm2 attributes)
- Join testdata to Bel_adm2 using ID column as join key.
- Go into Bel_adm2 Properties->Style
- Use Graduated classification once with 'testdata' and once with 'TESTDATA2'. Both columns are NULL for two features (ID 3 and 11), but the way they are mapped is different. testdata null values are ignored and the spatial feature not drawn, while TESTDATA2 null values are transformed to 0 and corresponding features are drawn.
For me the way the testdata null values are handled is the correct way, also since TESTDATA2 null values transformed to 0 will alter classification results (e.g. quantiles).
#3 Updated by Médéric RIBREUX almost 6 years ago
- Resolution set to fixed/implemented
- % Done changed from 0 to 100
- Status changed from Open to Closed
Hello, bug triage...
in QGIS 2.13 master, the bug seems to be fixed: I've got null values for both columns and the graduated renderer gives exactly the same classes with testdata and TESTDATA2.
I am closing this bug !