Plugin: Query language - wildcard (truncation) support
| Other versions of this plugin may exist. Please ensure you are viewing the documentation for the version that you are currently using. If you are not running the latest version of your plugin we recommend upgrading. See: list of all available versions of this plugin. |
Purpose
This plugin can be used to add limited wildcard (truncation) support to user queries. It allows you to use the asterisk operator on the right-hand side (only) of words in a query. Each word that is followed by an asterisk will be internally expanded into a set of words that start with indicated word.
When to use this plugin
This plugin should be used if you need to provide wildcard support in queries.
Once enabled, queries such as Dan* Smith or aus* directory pol* should now be accepted.
| This provides an efficient way of supporting wildcards - however the expanded query won’t return all the matching results (compared to if a full expansion of the wildcard was performed). There is a fine balancing act between performance and completeness of the search result set and the goal of a web search engine such as Funnelback has always been to return a set of relevant results. This set isn’t necessarily complete as shortcuts are taken to determine relevant results quickly. |
Usage
Enable the plugin
Enable the query-wildcard-supporton your results page from the Extensions screen in the administration dashboard or add the following data source configuration to enable the plugin.
plugin.query-wildcard-support.enabled=true
plugin.query-wildcard-support.version=1.0.1| The plugin will take effect as soon as it is enabled. |
Example
To set the maximum number of query terms to expand partial query as 6, configure the plugin with:
plugin.query-wildcard-support.config.partial_query_expansion_index=6Details
This plugin uses the auto-completion service to expand any words that are followed by an asterisk operator in a query.
The expanded queries can be seen by viewing the JSON or XML output and looking at the query/queryAsProcessed/queryRaw/querySystemRaw/queryCleaned values from the response packet. Expansions are injected into the querySystemRaw element.