Merge pull request #3590 from lonvia/lookup-per-osm-type

[nominatim.git] / docs / admin / Migration.md

diff --git a/docs/admin/Migration.md b/docs/admin/Migration.md
index 11ee7f0558c37406599d681334b602524492f363..13e6d7f5e5ce64629a37f58e5344cc774731bfea 100644 (file)
--- a/docs/admin/Migration.md
+++ b/docs/admin/Migration.md
@@ -1,21 +1,82 @@
 # Database Migrations
 
-Since version 3.7.0 Nominatim offers automatic migrations. Please follow
+Nominatim offers automatic migrations for versions 4.3+. Please follow
 the following steps:
 
-* stop any updates that are potentially running
-* update Nominatim to the newer version
-* go to your project directory and run `nominatim admin --migrate`
-* (optionally) restart updates
+* Stop any updates that are potentially running
+* Update the backend: `pip install -U nominatim-db`
+* Go to your project directory and run `nominatim admin --migrate`
+* Update the frontend: `pip install -U nominatim-api`
+* (optionally) Restart updates
+
+If you are still using CMake for the installation of Nominatim, then you
+need to update the software in one step before migrating the database.
+It is not recommended to do this while the machine is serving requests.
 
 Below you find additional migrations and hints about other structural and
 breaking changes. **Please read them before running the migration.**
 
 !!! note
-    If you are migrating from a version <3.6, then you still have to follow
-    the manual migration steps up to 3.6.
+    If you are migrating from a version <4.3, you need to install 4.3
+    first and migrate to 4.3 first. Then you can migrate to the current
+    version. It is strongly recommended to do a reimport instead.
+
+## 4.5.0 -> master
+
+### PHP frontend removed
+
+The PHP frontend has been completely removed. Please switch to the Python
+frontend.
+
+Without the PHP code, the `nominatim refresh --website` command is no longer
+needed. It currently omits a warning and does otherwise nothing. It will be
+removed in later versions of Nominatim. So make sure you remove it from your
+scripts.
+
+## 4.4.0 -> 4.5.0
+
+### New structure for Python packages
+
+The nominatim Python package has been split into `nominatim-db` and `nominatim-api`.
+Any imports need to be adapted accordingly.
+
+If you are running the Python frontend, change the server module from
+`nominatim.server.falcon.server` to `nominatim_api.server.falcon.server`.
+
+If you are using the Nominatim library, all imports need to be changed
+from `nominatim.api.<module>` to `nominatim_api.<module>`.
+
+If you have written custom tokenizers or sanitizers, the appropriate modules
+are now found in `nominatim_db`.
+
+## 4.2.0 -> 4.3.0
+
+### New indexes for reverse lookup
+
+The reverse lookup algorithm has changed slightly to improve performance.
+This change needs a different index in the database. The required index
+will be automatically build during migration. Until the new index is available
+performance of the /reverse endpoint is significantly reduced. You should
+therefore either remove traffic from the machine before attempting a
+version update or create the index manually **before** starting the update
+using the following SQL:
+
+```sql
+CREATE INDEX IF NOT EXISTS idx_placex_geometry_reverse_lookupPlaceNode
+  ON placex USING gist (ST_Buffer(geometry, reverse_place_diameter(rank_search)))
+  WHERE rank_address between 4 and 25 AND type != 'postcode'
+    AND name is not null AND linked_place_id is null AND osm_type = 'N';
+```
+
+## 4.0.0 -> 4.1.0
+
+### ICU tokenizer is the new default
 
-## 4.0.0 -> master
+Nominatim now installs the [ICU tokenizer](../customize/Tokenizers.md#icu-tokenizer)
+by default. This only has an effect on newly installed databases. When
+updating older databases, it keeps its installed tokenizer. If you still
+run with the legacy tokenizer, make sure to compile Nominatim with the
+PostgreSQL module, see [Installation](Installation.md#building-nominatim).
 
 ### geocodejson output changed