make sure that addr:* tags can always be searched for

Always add contents of addr:* tags into address part of the search
table, even when there is no corresponding other name. This keeps
search tolerant to the kind of tagging where parts show up in the
address that have no corresponding object in the database or where
it is only an unaddressable object.

sql/functions/normalization.sql

@@ -207,16 +207,22 @@ CREATE OR REPLACE FUNCTION addr_ids_from_name(lookup_word TEXT)
   AS $$
 DECLARE
   lookup_token TEXT;
+  id INTEGER;
   return_word_id INTEGER[];
 BEGIN
   lookup_token := make_standard_name(lookup_word);
   SELECT array_agg(word_id) FROM word
     WHERE word_token = lookup_token and class is null and type is null
     INTO return_word_id;
+  IF return_word_id IS NULL THEN
+    id := nextval('seq_word');
+    INSERT INTO word VALUES (id, lookup_token, null, null, null, null, 0);
+    return_word_id = ARRAY[id];
+  END IF;
   RETURN return_word_id;
 END;
 $$
-LANGUAGE plpgsql STABLE;
+LANGUAGE plpgsql;
 
 
 -- Normalize a string and look up its name ids (full words).