Made the limit configurable with an optional argument, updating the testing as well to reflect this. default is now 0, meaning that it will return everything that occurs more than once. Removed mock database test, and got rid of fetch all. Rebased all tests to monkeypatch

src/nominatim_db/tools/special_phrases/sp_importer.py

@@ -64,23 +64,25 @@ class SPImporter():
         # special phrases class/type on the wiki.
         self.table_phrases_to_delete: Set[str] = set()
 
-    def get_classtype_pairs(self) -> Set[Tuple[str, str]]:
+    def get_classtype_pairs(self, min: int = 0) -> Set[Tuple[str, str]]:
         """
             Returns list of allowed special phrases from the database,
             restricting to a list of combinations of classes and types
-            which occur more than 100 times
+            which occur more than a specified amount of times.
+
+            Default value for this, if not specified, is at least once.
         """
         db_combinations = set()
-        query = """
+        query = f"""
         SELECT class AS CLS, type AS typ
         FROM placex
         GROUP BY class, type
-        HAVING COUNT(*) > 100
+        HAVING COUNT(*) > {min}
         """
 
         with self.db_connection.cursor() as db_cursor:
             db_cursor.execute(SQL(query))
-            for row in db_cursor.fetchall():
+            for row in db_cursor:
                 db_combinations.add((row[0], row[1]))
 
         return db_combinations