Nominatim/Version2

Changes

Indexing

• Merge admin boundaries and place nodes (where within 2 levels of rank)
• Modify Voronoi algorithm to take account of known fixed boundaries
• Native postgresql Voronoi
• Additional per-country index to speed up searches within country - might require better county polygons in OSM?
• Various problems with German postfixes / abbreviations
• Performance - indexing is far too slow. Test clustering and polygon generation to see effects
• Move to hstore for name storage for compatibility
• Import minute change sets so index fully up to date
• (TODO) Assign UUID to features. Ideally UUID should be consistent between nominatim systems! (is that even possible?!?)
• (TODO) Generate indexes in memory

Search

• (TODO) Re-write search logic in java.
• Use statistics to estimate phrase importance to improve ordering of search graph
• Change all scoring functions to a 0 to 1 scale so scores can be calculated using multiple factors
• Re-score strings after index search (index is lossy, we should recheck - perfect matches should beat transliterations)
• (TODO) Options for fallback to high level feature when low level features missing (i.e. town when street not yet present)
• (TODO) 'Did you means' Suggestions. Can't use standard - too many words and phrases (too slow) - so:
  • High level admin features only?
  • Modified levenshtein btree?
  • Geographic indexing of suggestions?
  • Word context based indexing?
• Allow detailed / structured search terms in query (i.e. country=DE&city=Berlin)
• (partially done) Search for amenities by tag pair
• Search graph to take account of in / nearest rather than just dropping them (partially done)
• Multilingual support for nearest / in / im (possible list of words in wiki (Name_finder:Translations)
• (TODO) Searching for street intersections
• (FAILED) Provide option to use postgresql full text search module as alternative indexing method
• (TODO) Better formatting of address output (address format def on wiki? crowdsource?)
• (TODO) Indexing support for autocomplete text entry (prefix search)

Code

(TODO) Re-factor and reorganise the code - its a bit of a mess!

Gazetteer Output

• Minor index change required to make this efficient, but requires complete re-index of planet
• xml interface
• Visual representation of address 'graph' to help people debug

Export

• (TODO) Provide export files (xml?) at various detail levels
  • Structured? (in progress)
  • Flat?
• (TODO) Provide postgresql dump file to get people started?