penalize search with frequent partials

[nominatim.git] / nominatim / api / search / db_search_builder.py

diff --git a/nominatim/api/search/db_search_builder.py b/nominatim/api/search/db_search_builder.py
index 2a3153be334d17ed3262853cd156172febb0f8b3..ee06dba5ef95f916bceb10edc9148366a1ba0d8b 100644 (file)
--- a/nominatim/api/search/db_search_builder.py
+++ b/nominatim/api/search/db_search_builder.py
@@ -163,6 +163,7 @@ class SearchBuilder:
         sdata.lookups = [dbf.FieldLookup('name_vector', [t.token for t in hnrs], 'lookup_any'),
                          dbf.FieldLookup('nameaddress_vector', partial_tokens, 'lookup_all')
                         ]
+        sdata.housenumbers = dbf.WeightedStrings([], [])
         yield dbs.PlaceSearch(0.05, sdata, sum(t.count for t in hnrs))
 
 
@@ -219,14 +220,12 @@ class SearchBuilder:
 
         # Partial term to frequent. Try looking up by rare full names first.
         name_fulls = self.query.get_tokens(name, TokenType.WORD)
-        rare_names = list(filter(lambda t: t.count < 1000, name_fulls))
+        rare_names = list(filter(lambda t: t.count < 10000, name_fulls))
         # At this point drop unindexed partials from the address.
         # This might yield wrong results, nothing we can do about that.
         if not partials_indexed:
             addr_tokens = [t.token for t in addr_partials if t.is_indexed]
-            log().var_dump('before', penalty)
             penalty += 1.2 * sum(t.penalty for t in addr_partials if not t.is_indexed)
-            log().var_dump('after', penalty)
         if rare_names:
             # Any of the full names applies with all of the partials from the address
             lookup = [dbf.FieldLookup('name_vector', [t.token for t in rare_names], 'lookup_any')]
@@ -248,8 +247,12 @@ class SearchBuilder:
                 lookup = [dbf.FieldLookup('name_vector', non_rare_names, 'lookup_any')]
             if addr_tokens:
                 lookup.append(dbf.FieldLookup('nameaddress_vector', addr_tokens, 'lookup_all'))
-            yield penalty + 0.1 * max(0, 5 - len(name_partials) - len(addr_tokens)),\
-                  min(exp_name_count, exp_addr_count), lookup
+            penalty += 0.1 * max(0, 5 - len(name_partials) - len(addr_tokens))
+            if len(rare_names) == len(name_fulls):
+                # if there already was a search for all full tokens,
+                # avoid this if anything has been found
+                penalty += 0.25
+            yield penalty, min(exp_name_count, exp_addr_count), lookup
 
 
     def get_name_ranking(self, trange: TokenRange) -> dbf.FieldRanking: