Layers become non-editable

[infobleep]

Whilst working on a map containing a mixture Ordnance Survey ITN data and other data, two of layers I was wondering on suddenly could not be edited. These were railway and road ITN layers. The only way I could get them to become editable was to add in another copy of the ITN roads layer. This then allowed the other two layers to be edited. However once I removed the additional ITN roads layer, the previously non-editable layers only remained editable until editing was toggled off. Once off the editing couldn't be toggled on without the ITN roads layer being reinserted once again. Even shut down and restarting Quantum did not help.

I cannot supply the data layers as this would breech the terms of the OS license.

[infobleep]

Quantum GIS file - for license reasons I cannot supply the shape files that couldn't be edited

[jef]

Shapefiles with queries (like raods_for_text) are not editable. This is an OGR restriction.

Feel free to reopen, when this isn't limited to filtered layers.

[infobleep]

Replying to jef:

Shapefiles with queries (like raods_for_text) are not editable. This is an OGR restriction.

Feel free to reopen, when this isn't limited to filtered layers.

If that is the case, why can I edit when the same layer has been added in a second time? If the restriction applies it should apply no matter how many copies of the same lyaer I've added to the Quantum document. Therefore I believe there must be a bug. If what I report isn't a bug, then the fact it's possible to edit when it shouldn't be allowed is the bug, if that makes sense.

[jef]

Replying to infobleep:

Replying to jef:

Shapefiles with queries (like raods_for_text) are not editable. This is an OGR restriction.

If that is the case, why can I edit when the same layer has been added in a second time?

Without a query you can edit the shape, but with a query you can't.

What could be considered a bug is that you can apply a query on any shape layer, that already is in editing mode.

OTOH that change of editing capability is purely up to the OGR shape driver and might change in the future. Other OGR datasources might behave different and other qgis data providers like the postgres provider actually do.

[infobleep]

Replying to jef:

Replying to infobleep:

Replying to jef:

Shapefiles with queries (like raods_for_text) are not editable. This is an OGR restriction.

If that is the case, why can I edit when the same layer has been added in a second time?

Without a query you can edit the shape, but with a query you can't.

What could be considered a bug is that you can apply a query on any shape layer, that already is in editing mode.

OTOH that change of editing capability is purely up to the OGR shape driver and might change in the future. Other OGR datasources might behave different and other qgis data providers like the postgres provider actually do.

Sorry Jef, I misunderstood your original reply. A query is set up to allow different layers to be generated from one data source. A data source containing roads might have 5 different road types. So I used queries to create 5 layers, one for each road type. This then would allow label the text for each road type with a different style. Whilst doing this though, I may still wish to edit the roads in the original datasource.

I could add in another copy of the datasource layer without a query placed on it but that would be more confusing for users with less understanding of GIS.