reindex postcodes that loose their parents

When the parent place of a postcode is deleted, it needs to
be reindexed to get a new parent. Otherwise displaying of
results is broken.

nominatim/clicmd/index.py

@@ -56,6 +56,7 @@ class UpdateIndex:
             indexer.index_boundaries(args.minrank, args.maxrank)
         if not args.boundaries_only:
             indexer.index_by_rank(args.minrank, args.maxrank)
+            indexer.index_postcodes()
 
         if not args.no_boundaries and not args.boundaries_only \
            and args.minrank == 0 and args.maxrank == 30:

nominatim/tools/migration.py

@@ -384,7 +384,7 @@ def add_improved_geometry_reverse_placenode_index(conn: Connection, **_: Any) ->
                     """)
 
 @_migration(4, 4, 99, 0)
-def create_postcode_ara_lookup_index(conn: Connection, **_: Any) -> None:
+def create_postcode_area_lookup_index(conn: Connection, **_: Any) -> None:
     """ Create index needed for looking up postcode areas from postocde points.
     """
     with conn.cursor() as cur:
@@ -392,3 +392,14 @@ def create_postcode_ara_lookup_index(conn: Connection, **_: Any) -> None:
                        ON placex USING BTREE (country_code, postcode)
                        WHERE osm_type = 'R' AND class = 'boundary' AND type = 'postal_code'
                     """)
+
+
+@_migration(4, 4, 99, 1)
+def create_postcode_parent_index(conn: Connection, **_: Any) -> None:
+    """ Create index needed for updating postcodes when a parent changes.
+    """
+    if conn.table_exists('planet_osm_ways'):
+        with conn.cursor() as cur:
+            cur.execute("""CREATE INDEX IF NOT EXISTS
+                             idx_location_postcode_parent_place_id
+                             ON location_postcode USING BTREE (parent_place_id)""")

nominatim/version.py

@@ -34,7 +34,7 @@ class NominatimVersion(NamedTuple):
         return f"{self.major}.{self.minor}.{self.patch_level}-{self.db_patch_level}"
 
 
-NOMINATIM_VERSION = NominatimVersion(4, 4, 99, 0)
+NOMINATIM_VERSION = NominatimVersion(4, 4, 99, 1)
 
 POSTGRESQL_REQUIRED_VERSION = (9, 6)
 POSTGIS_REQUIRED_VERSION = (2, 2)