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</o:shapelayout></xml><![endif]--></head><body lang=DE link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Hello list,<o:p></o:p></p><p class=MsoNormal>hello Anna, Helmut, Moritz, and Aldo<o:p></o:p></p><p class=MsoNormal>I’d like to say thanks for the helpful tips on my questions concerning the data model. Especially Aldo’s explanations helped me such a lot, thank you once more. I appreciate it very much. It was possible for me to get deeper into the backgrounds by taking a look at the ascii representation of the GRASS data structure and by studying Aldo’s figures.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>ASCII export makes layer structure, categories and element types visible and thus understandable.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>But I still think that the layer concept is nothing unique or special in this GRASS data model. If you „rename“ the layers (that is: set layer1=column1 and layer2=column2) and put the columns in a shapefile (for example), then you have exactly the same chances to relate shape data to different external files via the different columns, while the geometric feature is digitized only one time. Or am I wrong? I know that shapes are different because they hold only one type at a time, but that don’t matter here.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Best regards, Uwe<span style='font-family:"Verdana",sans-serif'><o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Verdana",sans-serif'><o:p> </o:p></span></p></div></body></html>