featuresmergeqgis
I have a large feature dataset with thousands of entries. Each entry is represented by a polygon. The most have unique values in all fields but some of them have to be merged based on a identity number in a field (zip code). I want to merge these polygons without losing the other field values. Is there a operation for this in QGIS?
here is a a screenshot of the aggregate function:
What you are calling a Merge appears to be what I would use the Join Field tool for because it ...
Joins the contents of a table to another table based on a common attribute field. The input table is updated to contain the fields from the join table. You can select which fields from the join table will be added to the input table.
Dissolve is the tool you are looking for.
Data Management Tools -> Generalization -> Dissolve
Be sure to uncheck "Create multipart features" as @felixip noted in his comment.
Best Answer
You can use
Menu Processing / Toolbox / Aggregatefor this. See the documentation: https://docs.qgis.org/3.16/en/docs/user_manual/processing_algs/qgis/vectorgeometry.html#aggregateTo keep all attribute values, you can concatenate them. This works well for string (text) fields. If you have integers, you must convert them to string using
to_string("attribute")(replaceattributewith the name of the respective attribute). Don't forget to set the resulting field-type to text and define a field-length long enough to include all values: