Untagged unconnected node

An untagged unconnected node is a node which is not part of any ways or relations (unconnected) and which does not have any tags on it. Since this cannot possibly represent anything, there is no reason for such a node to exist in the data. However when uploading data to the database there will first be uploaded the nodes and only later the ways where they are contained, hence resulting in empty nodes for the time the upload is not finished. Please consider that big uploads might go on for hours or even days.

If older than several days it is a bug, and should be deleted

Quality Assurance

Various Quality Assurance tools will detect this type of bug (along with many other types). Maplint shows them in orange for example.

Where do empty nodes come from

A line of untagged unconnected nodes may be caused by editors failing to complete an upload of a way. Since the introduction of changesets, this is less likely to occur, since the operations to create nodes and then connect them as a way, are rolled into one request and one DB transaction.

Empty nodes might also come from users that created the node and forgot to tag it.

Some users use 3 nodes in a row to express something like "..." (an unsurveyed diverging road or a continuing road not yet in the db).

Further reading

A discussion about these nodes can be found on the mailing list: RFC: what are empty nodes and how should we use them?

See also: Key:fixme