[QGIS-trac] Re: [Quantum GIS] #1638: copy/paste of attributes/layers (merge) gives unexpected results(?)

[Quantum GIS]

#1638: copy/paste of attributes/layers (merge) gives unexpected results(?)
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        Reporter:  lutra                            |         Owner:               
            Type:  enhancement                      |        Status:  new          
        Priority:  minor: annoyance or enhancement  |     Milestone:  Version 1.1.0
       Component:  Vectors                          |       Version:  HEAD         
      Resolution:                                   |      Keywords:               
Platform_version:                                   |      Platform:  All          
        Must_fix:  No                               |   Status_info:  0            
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Changes (by jef):

  * milestone:  Version 1.0.2 => Version 1.1.0
  * priority:  major: does not work as expected => minor: annoyance or
               enhancement
  * platform:  Debian => All
  * must_fix:  Yes => No
  * owner:  jef =>
  * type:  bug => enhancement

Comment:

 Replying to [ticket:1638 lutra]:
 > A common definition of "Merge" of layers is the following:
 [...]

 > Actually seems to me that the only way to merge two or more layers in
 QGIS is to copy/paste (all the) features to an existing layer or to a new
 empty one.

 I wouldn't expect that to generally work.  IMHO pasting features to a
 layer should _NOT_ add any new attributes (ie. columns).

 Although I didn't check what currently happens, I'd expect that the
 attributes of the features to paste are just sequentially mapped to the
 attributes of the destination layer.

 If the datatypes of the original differ from the destination attributes
 that mapping might not work correctly and lead to problems when trying to
 commit the changes later.

 So I'd expect pasting to work only if source and destination layer are
 structually identical.

 You might find something like that in fTools - Union maybe.

-- 
Ticket URL: <https://trac.osgeo.org/qgis/ticket/1638#comment:3>
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