From df0b394c5973e524cfab02bc404288533da8dcd7 Mon Sep 17 00:00:00 2001
From: Itz-Agasta <rupamgolui69@gmail.com>
Date: Thu, 6 Aug 2026 14:32:07 +0530
Subject: [PATCH] Drop the place_classtype tables on migration

Nothing creates or reads them anymore, so a migrated database would keep
carrying them around for nothing. On a planet that is 428 tables and a
good 8GB.

The migration runs after the POI backfill, which still needs the table
names to work out which rows to fill in.
---
 docs/admin/Migration.md             | 12 ++++++++++++
 src/nominatim_db/tools/migration.py | 19 ++++++++++++++++++-
 src/nominatim_db/version.py         |  2 +-
 3 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/docs/admin/Migration.md b/docs/admin/Migration.md
index da44c07f..3b8ebc2f 100644
--- a/docs/admin/Migration.md
+++ b/docs/admin/Migration.md
@@ -17,6 +17,18 @@ breaking changes. **Please read them before running the migration.**
     and migrate to 4.3 first. Then you can migrate to the current
     version. It is strongly recommended to do a reimport instead.
 
+## 5.3.0 -> 5.4.0
+
+### Removal of the place_classtype tables
+
+Category search now runs against the `categories` column of `placex`, so the
+per-category `place_classtype_*` tables are not used anymore. The migration
+drops them. This frees a considerable amount of disk space on a planet
+database but may take a moment as there is one table per category.
+
+The `--min` option of `nominatim special-phrases` only restricted which of
+those tables were created. It has no effect anymore and has been removed.
+
 ## 5.2.0 -> 5.3.0
 
 #### Expensive table migrations
diff --git a/src/nominatim_db/tools/migration.py b/src/nominatim_db/tools/migration.py
index 5fb88345..b2722141 100644
--- a/src/nominatim_db/tools/migration.py
+++ b/src/nominatim_db/tools/migration.py
@@ -13,7 +13,7 @@ import logging
 from ..errors import UsageError
 from ..config import Configuration
 from ..db import properties
-from ..db.connection import connect, Connection, \
+from ..db.connection import connect, Connection, drop_tables, \
                             table_exists, register_hstore, table_has_column
 from ..db.sql_preprocessor import SQLPreprocessor
 from ..version import NominatimVersion, NOMINATIM_VERSION, parse_version
@@ -684,3 +684,20 @@ def add_centroid_categories_index(conn: Connection, **_: Any) -> None:
     conn.execute("""CREATE INDEX IF NOT EXISTS idx_placex_centroid_categories
                     ON placex USING GIST (centroid,
                                           categories gist__ltree_ops(siglen=8))""")
+
+
+@_migration(5, 3, 99, 4)
+def drop_place_classtype_tables(conn: Connection, **_: Any) -> None:
+    """ Drop the obsolete place_classtype_* tables.
+
+    Category search now goes through the ltree categories column, so nothing
+    reads these tables anymore. They are dropped after the POI backfill above,
+    which still uses their names to decide which rows to fill in.
+    """
+    with conn.cursor() as cur:
+        cur.execute("""SELECT tablename FROM pg_tables
+                       WHERE schemaname = 'public'
+                             AND tablename LIKE 'place\\_classtype\\_%'""")
+        tables = [row[0] for row in cur]
+
+    drop_tables(conn, *tables)
diff --git a/src/nominatim_db/version.py b/src/nominatim_db/version.py
index 3a2c83ad..e512d216 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('5.3.99-3')
+NOMINATIM_VERSION = parse_version('5.3.99-4')
 
 POSTGRESQL_REQUIRED_VERSION = (13, 0)
 POSTGIS_REQUIRED_VERSION = (3, 0)
-- 
2.47.3