From cd843860045561728d6b5bd08edf44beb86163f9 Mon Sep 17 00:00:00 2001
From: Sarah Hoffmann <lonvia@denofr.de>
Date: Mon, 9 Mar 2026 10:10:28 +0100
Subject: [PATCH] add migration to backfill missing importance values

---
 src/nominatim_db/tools/migration.py | 19 ++++++++++++++++++-
 src/nominatim_db/version.py         |  2 +-
 2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/src/nominatim_db/tools/migration.py b/src/nominatim_db/tools/migration.py
index 7d8e8ce9..bedccb8a 100644
--- a/src/nominatim_db/tools/migration.py
+++ b/src/nominatim_db/tools/migration.py
@@ -14,7 +14,7 @@ from ..errors import UsageError
 from ..config import Configuration
 from ..db import properties
 from ..db.connection import connect, Connection, \
-                            table_exists, register_hstore
+                            table_exists, register_hstore, table_has_column
 from ..db.sql_preprocessor import SQLPreprocessor
 from ..version import NominatimVersion, NOMINATIM_VERSION, parse_version
 from ..tokenizer import factory as tokenizer_factory
@@ -420,3 +420,20 @@ def create_place_interpolation_table(conn: Connection, config: Configuration, **
               SET type = coalesce(address->'interpolation', 'all'),
                   address = address - 'interpolation'::TEXT;
             """)
+
+
+@_migration(5, 2, 99, 4)
+def backfill_importance(conn: Connection, **_: Any) -> None:
+    """ Backfill missing importance values.
+    """
+    conn.execute("""UPDATE placex
+                    SET importance = 0.40001 - (rank_search::float / 75)
+                    WHERE importance is NULL OR importance <= 0
+                 """)
+    if table_exists(conn, 'search_name')\
+       and table_has_column(conn, 'search_name', 'search_rank'):
+        conn.execute("""UPDATE search_name
+                        SET importance = 0.40001 - (search_rank::float / 75)
+                        WHERE importance is NULL OR importance <= 0
+                     """)
+        conn.execute("ALTER TABLE search_name DROP COLUMN search_rank")
diff --git a/src/nominatim_db/version.py b/src/nominatim_db/version.py
index 761803c1..b730d95f 100644
--- a/src/nominatim_db/version.py
+++ b/src/nominatim_db/version.py
@@ -55,7 +55,7 @@ def parse_version(version: str) -> NominatimVersion:
     return NominatimVersion(*[int(x) for x in parts[:2] + parts[2].split('-')])
 
 
-NOMINATIM_VERSION = parse_version('5.2.99-3')
+NOMINATIM_VERSION = parse_version('5.2.99-4')
 
 POSTGRESQL_REQUIRED_VERSION = (12, 0)
 POSTGIS_REQUIRED_VERSION = (3, 0)