+# Importing and Updating the Database
+
The following instructions explain how to create a Nominatim database
from an OSM planet file and how to keep the database up to date. It
is assumed that you have already successfully installed the Nominatim
software itself, if not return to the [installation page](Installation.md).
-# Configuration setup in settings/local.php
+## Configuration setup in settings/local.php
The Nominatim server can be customized via the file `settings/local.php`
in the build directory. Note that this is a PHP file, so it must always
There are lots of configuration settings you can tweak. Have a look
at `settings/default.php` for a full list. Most should have a sensible default.
-### Flatnode files
+#### Flatnode files
If you plan to import a large dataset (e.g. Europe, North America, planet),
you should also enable flatnode storage of node locations. With this
Replace the second part with a suitable path on your system and make sure
the directory exists. There should be at least 40GB of free space.
-# Downloading additional data
+## Downloading additional data
-## Wikipedia rankings
+### Wikipedia rankings
Wikipedia can be used as an optional auxiliary data source to help indicate
-the importance of osm features. Nominatim will work without this information
+the importance of OSM features. Nominatim will work without this information
but it will improve the quality of the results if this is installed.
This data is available as a binary download:
wget https://www.nominatim.org/data/wikipedia_redirect.sql.bin
Combined the 2 files are around 1.5GB and add around 30GB to the install
-size of nominatim. They also increase the install time by an hour or so.
+size of Nominatim. They also increase the install time by an hour or so.
*NOTE:* you'll need to download the Wikipedia rankings before performing
the initial import of the data if you want the rankings applied to the
loaded data.
-## UK postcodes
+### UK postcodes
-Nominatim can use postcodes from an external source to improve searches that involve a UK postcode. This data can be optionally downloaded:
+Nominatim can use postcodes from an external source to improve searches that involve a UK postcode. This data can be optionally downloaded:
cd $NOMINATIM_SOURCE_DIR/data
wget https://www.nominatim.org/data/gb_postcode_data.sql.gz
+## Choosing the Data to Import
+
+In its default setup Nominatim is configured to import the full OSM data
+set for the entire planet. Such a setup requires a powerful machine with
+at least 32GB of RAM and around 800GB of SSD hard disks. Depending on your
+use case there are various ways to reduce the amount of data imported. This
+section discusses these methods. They can also be combined.
+
+### Using an extract
+
+If you only need geocoding for a smaller region, then precomputed extracts
+are a good way to reduce the database size and import time.
+[Geofabrik](https://download.geofabrik.de) offers extracts for most countries.
+They even have daily updates which can be used with the update process described
+below. There are also
+[other providers for extracts](https://wiki.openstreetmap.org/wiki/Planet.osm#Downloading).
+
+Please be aware that some extracts are not cut exactly along the country
+boundaries. As a result some parts of the boundary may be missing which means
+that Nominatim cannot compute the areas for some administrative areas.
+
+### Dropping Data Required for Dynamic Updates
+
+About half of the data in Nominatim's database is not really used for serving
+the API. It is only there to allow the data to be updated from the latest
+changes from OSM. For many uses these dynamic updates are not really required.
+If you don't plan to apply updates, the dynamic part of the database can be
+safely dropped using the following command:
+
+```
+./utils/setup.php --drop
+```
+
+Note that you still need to provide for sufficient disk space for the initial
+import. So this option is particularly interesting if you plan to transfer the
+database or reuse the space later.
+
+### Reverse-only Imports
+
+If you only want to use the Nominatim database for reverse lookups or
+if you plan to use the installation only for exports to a
+[photon](https://photon.komoot.de/) database, then you can set up a database
+without search indexes. Add `--reverse-only` to your setup command above.
+
+This saves about 5% of disk space.
+
+### Filtering Imported Data
+
+Nominatim normally sets up a full search database containing administrative
+boundaries, places, streets, addresses and POI data. There are also other
+import styles available which only read selected data:
-# Initial import of the data
+* **settings/import-admin.style**
+ Only import administrative boundaries and places.
+* **settings/import-street.style**
+ Like the admin style but also adds streets.
+* **settings/import-address.style**
+ Import all data necessary to compute addresses down to house number level.
+* **settings/import-full.style**
+ Default style that also includes points of interest.
-**Important:** first try the import with a small excerpt, for example from
+The style can be changed with the configuration `CONST_Import_Style`.
+
+To give you an idea of the impact of using the different styles, the table
+below gives rough estimates of the final database size after import of a
+2018 planet and after using the `--drop` option. It also shows the time
+needed for the import on a machine with 32GB RAM, 4 CPUS and SSDs. Note that
+the given sizes are just an estimate meant for comparison of style requirements.
+Your planet import is likely to be larger as the OSM data grows with time.
+
+style | Import time | DB size | after drop
+----------|--------------|------------|------------
+admin | 5h | 190 GB | 20 GB
+street | 42h | 400 GB | 180 GB
+address | 59h | 500 GB | 260 GB
+full | 80h | 575 GB | 300 GB
+
+You can also customize the styles further. For an description of the
+style format see [the development section](../develop/Import.md).
+
+## Initial import of the data
+
+**Important:** first try the import with a small extract, for example from
[Geofabrik](https://download.geofabrik.de).
-Download the data to import and load the data with the following command:
+Download the data to import and load the data with the following command
+from the build directory:
```sh
./utils/setup.php --osm-file <data file> --all [--osm2pgsql-cache 28000] 2>&1 | tee setup.log
2/3 of RAM available. If your machine starts swapping reduce the size.
Computing word frequency for search terms can improve the performance of
-forward geocoding in particular under high load as it helps Postgres' query
+forward geocoding in particular under high load as it helps PostgreSQL's query
planner to make the right decisions. To recompute word counts run:
```sh
Note that this command downloads the phrases from the wiki link above.
-# Installing Tiger housenumber data for the US
-
-Nominatim is able to use the official TIGER address set to complement the
-OSM house number data in the US. You can add TIGER data to your own Nominatim
-instance by following these steps:
+## Installing Tiger housenumber data for the US
- 1. Install the GDAL library and python bindings and the unzip tool
+Nominatim is able to use the official [TIGER](https://www.census.gov/geo/maps-data/data/tiger.html)
+address set to complement the OSM house number data in the US. You can add
+TIGER data to your own Nominatim instance by following these steps. The
+entire US adds about 10GB to your database.
- * Ubuntu: `sudo apt-get install python-gdal unzip`
- * CentOS: `sudo yum install gdal-python unzip`
-
- 2. Get preprocessed TIGER 2015 data and unpack it into the
+ 1. Get preprocessed TIGER 2018 data and unpack it into the
data directory in your Nominatim sources:
cd Nominatim/data
- wget https://nominatim.org/data/tiger2017-nominatim-preprocessed.tar.gz
- tar xf tiger2017-nominatim-preprocessed.tar.gz
+ wget https://nominatim.org/data/tiger2018-nominatim-preprocessed.tar.gz
+ tar xf tiger2018-nominatim-preprocessed.tar.gz
+
+ `data-source/us-tiger/README.md` explains how the data got preprocessed.
- 3. Import the data into your Nominatim database:
+ 2. Import the data into your Nominatim database:
./utils/setup.php --import-tiger-data
- 4. Enable use of the Tiger data in your `settings/local.php` by adding:
+ 3. Enable use of the Tiger data in your `settings/local.php` by adding:
@define('CONST_Use_US_Tiger_Data', true);
- 5. Apply the new settings:
+ 4. Apply the new settings:
```sh
./utils/setup.php --create-functions --enable-diff-updates --create-partition-functions
```
-The entire US adds about 10GB to your database.
-
-You can also process the data from the original TIGER data to create the
-SQL files, Nominatim needs for the import:
-
- 1. Get the TIGER 2017 data. You will need the EDGES files
- (3,234 zip files, 11GB total). Choose one of the two sources:
-
- wget -r ftp://ftp2.census.gov/geo/tiger/TIGER2017/EDGES/
- wget -r ftp://mirror1.shellbot.com/census/geo/tiger/TIGER2017/EDGES/
-
- The first one is the original source, the second a considerably faster
- mirror.
-
- 2. Convert the data into SQL statements:
-
- ./utils/imports.php --parse-tiger <tiger edge data directory>
-
-Be warned that this can take quite a long time. After this process is finished,
-the same preprocessed files as above are available in `data/tiger`.
-# Updates
+## Updates
-There are many different possibilities to update your Nominatim database.
+There are many different ways to update your Nominatim database.
The following section describes how to keep it up-to-date with Pyosmium.
For a list of other methods see the output of `./utils/update.php --help`.
-### Installing the newest version of Pyosmium
+#### Installing the newest version of Pyosmium
It is recommended to install Pyosmium via pip. Run (as the same user who
will later run the updates):
pip install --user osmium
```
-Nominatim needs a tool called `pyosmium-get-updates` that comes with
+Nominatim needs a tool called `pyosmium-get-updates`, which comes with
Pyosmium. You need to tell Nominatim where to find it. Add the
following line to your `settings/local.php`:
The path above is fine if you used the `--user` parameter with pip.
Replace `user` with your user name.
-### Setting up the update process
+#### Setting up the update process
Next the update needs to be initialised. By default Nominatim is configured
to update using the global minutely diffs.
If you want a different update source you will need to add some settings
to `settings/local.php`. For example, to use the daily country extracts
-diffs for Ireland from geofabrik add the following:
+diffs for Ireland from Geofabrik add the following:
// base URL of the replication service
@define('CONST_Replication_Url', 'https://download.geofabrik.de/europe/ireland-and-northern-ireland-updates');
It outputs the date where updates will start. Recheck that this date is
what you expect.
-The --init-updates command needs to be rerun whenever the replication service
+The `--init-updates` command needs to be rerun whenever the replication service
is changed.
-### Updating Nominatim
+#### Updating Nominatim
The following command will keep your database constantly up to date:
projects / nominatim.git / blobdiff