linkedgeodata.org - RDFMapping

2011-04-29 10:37:57

Comparison for /RDF Mapping of 2011-04-29 10:37:57 and 2011-04-29 10:39:47

Additions:

Here we describe the mapping rules for converting Open Street Map data into RDF, and the filtering that is performed.

OSM-RDF-Mapping

2011-04-29 10:35:43

Comparison for /RDF Mapping of 2011-04-29 10:35:43 and 2011-04-29 10:37:57

Deletions:

Explanation coming soon.

2011-04-29 10:35:31

Comparison for /RDF Mapping of 2011-04-29 10:35:31 and 2011-04-29 10:35:43

Additions:

So in order to be performance-wise on the safe side, we have three filters in place:

Deletions:

So in order to be performance-wise on the safe side, we have a three filters in place:

2011-04-29 10:33:02

Comparison for /RDF Mapping of 2011-04-29 10:33:02 and 2011-04-29 10:35:31

Additions:

So in order to be performance-wise on the safe side, we have a three filters in place:

The EntityFilter rejects an OSM entity if any of its tags is blacklisted.
The TagFilter removes individual blacklisted tags from an entity but it does not reject the entity itself.
And eventually the RelevanceFilter only accepts entities of which any of its remaining tags is explicitly white listed.

Open Street Map entities (nodes and ways) currently need to pass all of these filters in order to end up in the dumps and the SPARQL-Endpoints. Additionally, ways with more than 20 nodes are rejected.

Deletions:

So in order to be performance-wise on the safe side, we have a three filters in place.
It consists of the EntityFilter, TagFilter, and RelevanceFilter.
Additionally, ways with more than 20 nodes are also rejected.
Open Street Map entities (nodes and ways) currently need to pass all of these filters in order to end up in the dumps and the SPARQL-Endpoints.

The EntityFilter rejects an OSM entity if any of its tags is blacklisted.
The TagFilter removes individual blacklisted tags from an entity but it does not reject the entity itself.
And eventually the RelevanceFilter only accepts entities of which any of its remaining tags is explicitly white listed.

2011-04-29 03:45:35

Comparison for /RDF Mapping of 2011-04-29 03:45:35 and 2011-04-29 10:33:02

Additions:

Deletions:

So in order to be performance-wise on the safe side, we have a three-staged filtering pipeline in place.
It consists of the EntityFilter, TagFilter, and RelevanceFilter. Open Street Map entities (nodes and ways) currently need to pass all of them in order to end up in the dumps and the SPARQL-Endpoints.

2011-04-29 03:44:48

Comparison for /RDF Mapping of 2011-04-29 03:44:48 and 2011-04-29 03:45:35

Additions:

The ± lets one choose between the following two interpretations:

Deletions:

The ± lets one chose between two interpretations:

2011-04-29 02:46:43

Comparison for /RDF Mapping of 2011-04-29 02:46:43 and 2011-04-29 03:44:48

Additions:

Each further row specifies a pattern of what tags to match.

Deletions:

Each further row defines the pattern of which tags that are affected.

2011-04-29 02:32:34

Comparison for /RDF Mapping of 2011-04-29 02:32:34 and 2011-04-29 02:46:43

Additions:

The current OSM-LGD mappings are configured with this XML file.
Actually this file is a sequence of serialized Java objects. The reason for this is hoped-for flexibility: If the need for a new mapping-type arises, there is a chance that it can be satisfied with a new implementation of a class.

Explanation coming soon.

Deletions:

We used heuristics to determine how certain tags in Open Street Map should be converted/mapped to RDF. The following XML mapping configuration file was created via such heuristics:
http://downloads.linkedgeodata.org/releases/current/OSM-LGD-Mappings.2010-07-15.rc1.xml.bz2

2011-04-29 02:30:33

Comparison for /RDF Mapping of 2011-04-29 02:30:33 and 2011-04-29 02:32:34

Additions:

The ± lets one chose between two interpretations:

+: Match any tag with the specified key and values
-: Match any tag with the specified key, except for those with the given values

Deletions:

The ± lets one chose between the two interpretations:
+ means: Match any tag with the specified key and values
– means: Match any tag with the specified key, except for those with the given values