add minimal documentation for the SQLite usage

[nominatim.git] / docs / customize / Settings.md

diff --git a/docs/customize/Settings.md b/docs/customize/Settings.md
index d080dc77b2f77ce5b18c705507ac40664f50a3d6..8245e309f1a476f0fba05d1df857002ddd6e06c3 100644 (file)
--- a/docs/customize/Settings.md
+++ b/docs/customize/Settings.md
@@ -91,7 +91,7 @@ The option is only used by the Legacy tokenizer and ignored otherwise.
 | --------------     | --------------------------------------------------- |
 | **Description:**   | Tokenizer used for normalizing and parsing queries and names |
 | **Format:**        | string |
 | --------------     | --------------------------------------------------- |
 | **Description:**   | Tokenizer used for normalizing and parsing queries and names |
 | **Format:**        | string |

-| **Default:**       | legacy |
+| **Default:**       | icu |

 | **After Changes:** | cannot be changed after import |
 
 Sets the tokenizer type to use for the import. For more information on
 | **After Changes:** | cannot be changed after import |
 
 Sets the tokenizer type to use for the import. For more information on


@@ -552,6 +552,8 @@ used.
 | **Format:**        | boolean |
 | **Default:**       | no |
 | **After Changes:** | run `nominatim refresh --website` |
 | **Format:**        | boolean |
 | **Default:**       | no |
 | **After Changes:** | run `nominatim refresh --website` |

+| **Comment:**       | PHP frontend only |
+

 
 This feature is currently undocumented and potentially broken.
 
 
 This feature is currently undocumented and potentially broken.
 


@@ -564,6 +566,7 @@ This feature is currently undocumented and potentially broken.
 | **Format:**        | integer |
 | **Default:**       | 500 |
 | **After Changes:** | run `nominatim refresh --website` |
 | **Format:**        | integer |
 | **Default:**       | 500 |
 | **After Changes:** | run `nominatim refresh --website` |

+| **Comment:**       | PHP frontend only |

 
 This setting defines the threshold over which a name is no longer considered
 as rare. When searching for places with rare names, only the name is used
 
 This setting defines the threshold over which a name is no longer considered
 as rare. When searching for places with rare names, only the name is used


@@ -604,6 +607,88 @@ with a single query.
 
 Setting this parameter to 0 disables polygon output completely.
 
 
 Setting this parameter to 0 disables polygon output completely.
 

+
+#### NOMINATIM_SEARCH_WITHIN_COUNTRIES
+
+| Summary            |                                                     |
+| --------------     | --------------------------------------------------- |
+| **Description:**   | Disable search for elements that are not in the country grid |
+| **Format:**        | boolean |
+| **Default:**       | no |
+| **After Changes:** | run `nominatim refresh --website` |
+| **Comment:**       | PHP frontend only |
+
+Enable to search elements just within countries.
+
+When enabled, if, despite not finding a point within the static grid of countries, it
+finds a geometry of a region, do not return the geometry.
+Return "Unable to geocode" instead.
+
+
+#### NOMINATIM_SERVE_LEGACY_URLS
+
+| Summary            |                                                     |
+| --------------     | --------------------------------------------------- |
+| **Description:**   | Enable serving via URLs with a .php suffix |
+| **Format:**        | boolean |
+| **Default:**       | yes |
+| **Comment:**       | Python frontend only |
+
+When enabled, then endpoints are reachable as `/<name>` as well as `/<name>.php`.
+This can be useful when you want to be backwards-compatible with previous
+versions of Nominatim.
+
+
+#### NOMINATIM_API_POOL_SIZE
+
+| Summary            |                                                     |
+| --------------     | --------------------------------------------------- |
+| **Description:**   | Number of parallel database connections per worker |
+| **Format:**        | number |
+| **Default:**       | 10 |
+| **Comment:**       | Python frontend only |
+
+Sets the maximum number of database connections available for a single instance
+of Nominatim. When configuring the maximum number of connections that your
+PostgreSQL database can handle, you need at least
+`NOMINATIM_API_POOL_SIZE` * `<number of configured workers>` connections.
+For configuring the number of workers, refer to the section about
+[Deploying the Python frontend](../admin/Deployment-Python.md).
+
+#### NOMINATIM_QUERY_TIMEOUT
+
+| Summary            |                                                     |
+| --------------     | --------------------------------------------------- |
+| **Description:**   | Timeout for SQL queries to the database |
+| **Format:**        | number (seconds) |
+| **Default:**       | 10 |
+| **Comment:**       | Python frontend only |
+
+When this timeout is set, then all SQL queries that run longer than the
+specified numbers of seconds will be cancelled and the user receives a
+timeout exceptions. Users of the API see a 503 HTTP error.
+
+The timeout does ont apply when using the
+[low-level DB access](../library/Low-Level-DB-Access.md)
+of the library. A timeout can be manually set, if required.
+
+
+#### NOMINATIM_REQUEST_TIMEOUT
+
+| Summary            |                                                     |
+| --------------     | --------------------------------------------------- |
+| **Description:**   | Timeout for search queries |
+| **Format:**        | number (seconds) |
+| **Default:**       | 60 |
+| **Comment:**       | Python frontend only |
+
+When this timeout is set, a search query will finish sending queries
+to the database after the timeout has passed and immediately return the
+results gathered so far.
+
+Note that under high load you may observe that users receive different results
+than usual without seeing an error. This may cause some confusion.
+

 ### Logging Settings
 
 #### NOMINATIM_LOG_DB
 ### Logging Settings
 
 #### NOMINATIM_LOG_DB


@@ -643,7 +728,24 @@ The entries in the log file have the following format:
     <request time> <execution time in s> <number of results> <type> "<query string>"
 
 Request time is the time when the request was started. The execution time is
     <request time> <execution time in s> <number of results> <type> "<query string>"
 
 Request time is the time when the request was started. The execution time is

-given in ms and corresponds to the time the query took executing in PHP.
+given in seconds and corresponds to the time the query took executing in PHP.

 type contains the name of the endpoint used.
 
 Can be used as the same time as NOMINATIM_LOG_DB.
 type contains the name of the endpoint used.
 
 Can be used as the same time as NOMINATIM_LOG_DB.

+
+#### NOMINATIM_DEBUG_SQL
+
+| Summary            |                                                     |
+| --------------     | --------------------------------------------------- |
+| **Description:**   | Enable printing of raw SQL by SQLAlchemy |
+| **Format:**        | boolean |
+| **Default:**       | no |
+| **Comment:**       | **For developers only.** |
+
+This settings enables
+[SQL debugging](https://docs.sqlalchemy.org/en/20/core/engines.html#dbengine-logging)
+by SQLAlchemy. This can be helpful when debugging some bugs with internal
+query handling. It should only be used together with the CLI query functions.
+Enabling it for server mode may have unintended consequences. Use the `debug`
+parameter instead, which prints information on how the search is executed
+including SQL statements.