Bug report #2629
fTools fail to rename duplicated field names if they are 10 char long
| Status: | Closed | ||
|---|---|---|---|
| Priority: | Low | ||
| Assignee: |  cfarmer - | ||
| Category: | Python plugins | ||
| Affected QGIS version: | Regression?: | No | |
| Operating System: | All | Easy fix?: | No |
| Pull Request or Patch supplied: | Resolution: | fixed | |
| Crashes QGIS or corrupts data: | Copied to github as #: | 12689 |
Description
If I join two tables containing common 10-char-long field name, fTools try to add the "_" char to one of them, then truncate it and fail to write, with no warning message. Could it rename the field name in a more robust way or at least warn that the layer won't be created and why?
add_warnings.diff 
- proposed patch
(7.33 KB)
trim_and_warnings.diff
(7.7 KB)
History
#1
Updated by Borys Jurgiel over 14 years ago
I've just realized it's a common issue in all fTools.
#2
Updated by Alexander Bruy over 14 years ago
This is not an fTools issue, this is limitation of ESRI Shapefile format (exactly DBF format). Field name must be <= 10 characters.
Here is patch to add some warnings to the "Join by attributes" and "Spatial join" tools
#3
Updated by Borys Jurgiel over 14 years ago
The warnings are necessary, but I still suggest to truncate names to 8 characters before adding the suffix. It's extremely easy to implement and can help in many cases (not in all, of course).
#4
Updated by Alexander Bruy over 14 years ago
Ok, here is another patch. Long names are truncated to 8 characters and then suffix added. But in this case warning are not necessary I think and we can remove it.
#5
Updated by Borys Jurgiel over 14 years ago
They're still necessary, as one can have more than 2 affected fields. E.g. both "foobarfoo1" and "foobarfoo2" in both tables. It would be the best to add a computed suffix _(n+1) (thought it's still not ideal, as it could cause confusions)
#6
Updated by Alexander Bruy over 14 years ago
Replying to [comment:6 borysiasty]:
It would be the best to add a computed suffix _(n+1) (thought it's still not ideal, as it could cause confusions)
As far as I see computed suffixes _(n+1) are used
#7
Updated by Borys Jurgiel over 14 years ago
Sorry, my fault! I've look too briefly into the code!
Anyway, I believe we should keep the warnings for a case if one has more than 9 very long names with common prefix in a non-dbf table (e.g. fobarfoo_temperature, fobarfoo_precipitation etc).
#8
Updated by cfarmer - over 14 years ago
- Resolution set to fixed
- Status changed from Open to Closed
Patch applied in 71a9f815 (SVN r13314).
Carson