]> git.openstreetmap.org Git - nominatim.git/blobdiff - nominatim/api/search/db_search_builder.py
skip lookup with full names when there are none
[nominatim.git] / nominatim / api / search / db_search_builder.py
index 2a3153be334d17ed3262853cd156172febb0f8b3..c755f2a74f8a16e2d53ca30503549040685d0046 100644 (file)
@@ -7,7 +7,7 @@
 """
 Convertion from token assignment to an abstract DB search.
 """
-from typing import Optional, List, Tuple, Iterator
+from typing import Optional, List, Tuple, Iterator, Dict
 import heapq
 
 from nominatim.api.types import SearchDetails, DataLayer
@@ -15,7 +15,6 @@ from nominatim.api.search.query import QueryStruct, Token, TokenType, TokenRange
 from nominatim.api.search.token_assignment import TokenAssignment
 import nominatim.api.search.db_search_fields as dbf
 import nominatim.api.search.db_searches as dbs
-from nominatim.api.logging import log
 
 
 def wrap_near_search(categories: List[Tuple[str, str]],
@@ -90,12 +89,14 @@ class SearchBuilder:
         if sdata is None:
             return
 
-        categories = self.get_search_categories(assignment)
+        near_items = self.get_near_items(assignment)
+        if near_items is not None and not near_items:
+            return # impossible compbination of near items and category parameter
 
         if assignment.name is None:
-            if categories and not sdata.postcodes:
-                sdata.qualifiers = categories
-                categories = None
+            if near_items and not sdata.postcodes:
+                sdata.qualifiers = near_items
+                near_items = None
                 builder = self.build_poi_search(sdata)
             elif assignment.housenumber:
                 hnr_tokens = self.query.get_tokens(assignment.housenumber,
@@ -103,18 +104,23 @@ class SearchBuilder:
                 builder = self.build_housenumber_search(sdata, hnr_tokens, assignment.address)
             else:
                 builder = self.build_special_search(sdata, assignment.address,
-                                                    bool(categories))
+                                                    bool(near_items))
         else:
             builder = self.build_name_search(sdata, assignment.name, assignment.address,
-                                             bool(categories))
+                                             bool(near_items))
 
-        if categories:
-            penalty = min(categories.penalties)
-            categories.penalties = [p - penalty for p in categories.penalties]
+        if near_items:
+            penalty = min(near_items.penalties)
+            near_items.penalties = [p - penalty for p in near_items.penalties]
             for search in builder:
-                yield dbs.NearSearch(penalty, categories, search)
+                search_penalty = search.penalty
+                search.penalty = 0.0
+                yield dbs.NearSearch(penalty + assignment.penalty + search_penalty,
+                                     near_items, search)
         else:
-            yield from builder
+            for search in builder:
+                search.penalty += assignment.penalty
+                yield search
 
 
     def build_poi_search(self, sdata: dbf.SearchData) -> Iterator[dbs.AbstractSearch]:
@@ -156,14 +162,27 @@ class SearchBuilder:
         """ Build a simple address search for special entries where the
             housenumber is the main name token.
         """
-        partial_tokens: List[int] = []
-        for trange in address:
-            partial_tokens.extend(t.token for t in self.query.get_partials_list(trange))
+        sdata.lookups = [dbf.FieldLookup('name_vector', [t.token for t in hnrs], 'lookup_any')]
+        expected_count = sum(t.count for t in hnrs)
+
+        partials = [t for trange in address
+                       for t in self.query.get_partials_list(trange)]
+
+        if expected_count < 8000:
+            sdata.lookups.append(dbf.FieldLookup('nameaddress_vector',
+                                                 [t.token for t in partials], 'restrict'))
+        elif len(partials) != 1 or partials[0].count < 10000:
+            sdata.lookups.append(dbf.FieldLookup('nameaddress_vector',
+                                                 [t.token for t in partials], 'lookup_all'))
+        else:
+            sdata.lookups.append(
+                dbf.FieldLookup('nameaddress_vector',
+                                [t.token for t
+                                 in self.query.get_tokens(address[0], TokenType.WORD)],
+                                'lookup_any'))
 
-        sdata.lookups = [dbf.FieldLookup('name_vector', [t.token for t in hnrs], 'lookup_any'),
-                         dbf.FieldLookup('nameaddress_vector', partial_tokens, 'lookup_all')
-                        ]
-        yield dbs.PlaceSearch(0.05, sdata, sum(t.count for t in hnrs))
+        sdata.housenumbers = dbf.WeightedStrings([], [])
+        yield dbs.PlaceSearch(0.05, sdata, expected_count)
 
 
     def build_name_search(self, sdata: dbf.SearchData,
@@ -187,69 +206,44 @@ class SearchBuilder:
             be searched for. This takes into account how frequent the terms
             are and tries to find a lookup that optimizes index use.
         """
-        penalty = 0.0 # extra penalty currently unused
-
+        penalty = 0.0 # extra penalty
         name_partials = self.query.get_partials_list(name)
-        exp_name_count = min(t.count for t in name_partials)
-        addr_partials = []
-        for trange in address:
-            addr_partials.extend(self.query.get_partials_list(trange))
+        name_tokens = [t.token for t in name_partials]
+
+        addr_partials = [t for r in address for t in self.query.get_partials_list(r)]
         addr_tokens = [t.token for t in addr_partials]
+
         partials_indexed = all(t.is_indexed for t in name_partials) \
                            and all(t.is_indexed for t in addr_partials)
+        exp_count = min(t.count for t in name_partials) / (2**(len(name_partials) - 1))
 
-        if (len(name_partials) > 3 or exp_name_count < 1000) and partials_indexed:
-            # Lookup by name partials, use address partials to restrict results.
-            lookup = [dbf.FieldLookup('name_vector',
-                                  [t.token for t in name_partials], 'lookup_all')]
-            if addr_tokens:
-                lookup.append(dbf.FieldLookup('nameaddress_vector', addr_tokens, 'restrict'))
-            yield penalty, exp_name_count, lookup
-            return
-
-        exp_addr_count = min(t.count for t in addr_partials) if addr_partials else exp_name_count
-        if exp_addr_count < 1000 and partials_indexed:
-            # Lookup by address partials and restrict results through name terms.
-            # Give this a small penalty because lookups in the address index are
-            # more expensive
-            yield penalty + exp_addr_count/5000, exp_addr_count,\
-                  [dbf.FieldLookup('name_vector', [t.token for t in name_partials], 'restrict'),
-                   dbf.FieldLookup('nameaddress_vector', addr_tokens, 'lookup_all')]
+        if (len(name_partials) > 3 or exp_count < 8000) and partials_indexed:
+            yield penalty, exp_count, dbf.lookup_by_names(name_tokens, addr_tokens)
             return
 
         # 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))
-        # 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:
+        if name_fulls:
+            fulls_count = sum(t.count for t in 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]
+                penalty += 1.2 * sum(t.penalty for t in addr_partials if not t.is_indexed)
             # 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')]
-            if addr_tokens:
-                lookup.append(dbf.FieldLookup('nameaddress_vector', addr_tokens, 'restrict'))
-            yield penalty, sum(t.count for t in rare_names), lookup
+            yield penalty, fulls_count / (2**len(addr_partials)),\
+                  dbf.lookup_by_any_name([t.token for t in name_fulls], addr_tokens,
+                                         'restrict' if fulls_count < 10000 else 'lookup_all')
 
         # To catch remaining results, lookup by name and address
         # We only do this if there is a reasonable number of results expected.
-        if min(exp_name_count, exp_addr_count) < 10000:
-            if all(t.is_indexed for t in name_partials):
-                lookup = [dbf.FieldLookup('name_vector',
-                                          [t.token for t in name_partials], 'lookup_all')]
-            else:
-                # we don't have the partials, try with the non-rare names
-                non_rare_names = [t.token for t in name_fulls if t.count >= 1000]
-                if not non_rare_names:
-                    return
-                lookup = [dbf.FieldLookup('name_vector', non_rare_names, 'lookup_any')]
+        exp_count = exp_count / (2**len(addr_partials)) if addr_partials else exp_count
+        if exp_count < 10000 and all(t.is_indexed for t in name_partials):
+            lookup = [dbf.FieldLookup('name_vector', name_tokens, 'lookup_all')]
             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 += 0.35 * max(0, 5 - len(name_partials) - len(addr_tokens))
+            yield penalty, exp_count, lookup
 
 
     def get_name_ranking(self, trange: TokenRange) -> dbf.FieldRanking:
@@ -337,8 +331,15 @@ class SearchBuilder:
                               self.query.get_tokens(assignment.postcode,
                                                     TokenType.POSTCODE))
         if assignment.qualifier:
-            sdata.set_qualifiers(self.query.get_tokens(assignment.qualifier,
-                                                       TokenType.QUALIFIER))
+            tokens = self.query.get_tokens(assignment.qualifier, TokenType.QUALIFIER)
+            if self.details.categories:
+                tokens = [t for t in tokens if t.get_category() in self.details.categories]
+                if not tokens:
+                    return None
+            sdata.set_qualifiers(tokens)
+        elif self.details.categories:
+            sdata.qualifiers = dbf.WeightedCategories(self.details.categories,
+                                                      [0.0] * len(self.details.categories))
 
         if assignment.address:
             sdata.set_ranking([self.get_addr_ranking(r) for r in assignment.address])
@@ -348,23 +349,22 @@ class SearchBuilder:
         return sdata
 
 
-    def get_search_categories(self,
-                              assignment: TokenAssignment) -> Optional[dbf.WeightedCategories]:
-        """ Collect tokens for category search or use the categories
+    def get_near_items(self, assignment: TokenAssignment) -> Optional[dbf.WeightedCategories]:
+        """ Collect tokens for near items search or use the categories
             requested per parameter.
             Returns None if no category search is requested.
         """
-        if assignment.category:
-            tokens = [t for t in self.query.get_tokens(assignment.category,
-                                                       TokenType.CATEGORY)
-                      if not self.details.categories
-                         or t.get_category() in self.details.categories]
-            return dbf.WeightedCategories([t.get_category() for t in tokens],
-                                          [t.penalty for t in tokens])
-
-        if self.details.categories:
-            return dbf.WeightedCategories(self.details.categories,
-                                          [0.0] * len(self.details.categories))
+        if assignment.near_item:
+            tokens: Dict[Tuple[str, str], float] = {}
+            for t in self.query.get_tokens(assignment.near_item, TokenType.NEAR_ITEM):
+                cat = t.get_category()
+                # The category of a near search will be that of near_item.
+                # Thus, if search is restricted to a category parameter,
+                # the two sets must intersect.
+                if (not self.details.categories or cat in self.details.categories)\
+                   and t.penalty < tokens.get(cat, 1000.0):
+                    tokens[cat] = t.penalty
+            return dbf.WeightedCategories(list(tokens.keys()), list(tokens.values()))
 
         return None