I work with this polygon and I try to use the vector tool "Singleparts to Multipart" in order to expload the layer to multipart, so I can select each part seperatly.
I don't care if the features in the attribute table has the same value. All I want is exploded layer:
and I get this error:
"At Least two features must contain the same attribute value"
I read Producing singlepart featureclass with unique IDs for each spatially non-connected polygon? ,but didn't get an answer