README.txt in Search API Database Search 7

Database search
---------------

This module provides a database based implementation of the Search API. The
database and target to use for storing and accessing the indexes can be selected
when creating a new server.

All Search API datatypes are supported by using appropriate SQL datatypes for
their respective columns (with "String"/"URI", and "Integer"/"Duration" being
equivalent).

The "direct" parse mode for queries will result in a simple splitting of the
query string into keys. Additionally, search keys containing whitespace will be
split, as searching for phrases is currently not supported.

Supported optional features
---------------------------

- search_api_autocomplete
  Introduced by module: search_api_autocomplete
  Lets you add autocompletion capabilities to search forms on the site. (See
  also "Hidden variables" below for backend-specific customization.)
  NOTE: Due to internal database restrictions, this will perform significantly
  better if only a single field is used for autocompletion.
- search_api_facets
  Introduced by module: search_api_facetapi
  Allows you to create facetted searches for dynamically filtering search
  results.

If you feel some service option is missing, or have other ideas for improving
this implementation, please file a feature request in the project's issue queue,
at [http://drupal.org/project/issues/search_api], using the "Database search"
component.

Known problems
--------------

Currently, Drupal doesn't support setting the table collation when creating
tables. This might cause problems when you want to index data which can contain
accented characters, umlauts and other non-ASCII characters (à, á, ä, …).
To resolve the issue, please set "utf8_bin" as the collation for all tables
starting with "search_api_db_". This has already been automated for MySQL
databases in newer releases but must be done manually for other databases.
See [1] for details.

[1] http://drupal.org/node/1144620

Also, using facets with a database server will only work if the database user
Drupal is using has the "CREATE TEMPORARY TABLES" permission (or similar, in
DBMSs other than MySQL).

Developer information
---------------------

Database queries for searches with this module are tagged with
"search_api_db_search" to allow easy altering. As metadata, such database
queries will have the Search API query object set as "search_api_query", and the
field settings of the server for the corresponding search index as
"search_api_db_fields".

Hidden variables
----------------

- search_api_db_autocomplete_max_occurrences (default: 0.9)
  By default, keywords that occur in more than 90% of results are ignored for
  autocomplete suggestions. This setting lets you modify that behaviour by
  providing your own ratio. Use 1 or greater to use all suggestions.