The Additional Query Parameters query pipeline stage is used to set, append, and remove Solr query parameters. This stage takes a list of query parameters. Each parameter is specified as a triple consisting of parameter name, parameter value, and update policy. Available update policies are: replace, append, remove and default. The policy ‘default’ means that this parameter will be added only if it has not yet been set via the request or by a default specification in the Solr config file solrconfig.xml.

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Example Stage Specification

Set the response format to JSON: 
{ "type":"set-params",
   "id":"default-params",
   "params": [
      {"key":"wt", "value":"json", "policy":"default"}
     ],
   "skip":false
}
Return a field named “id”, and 10 rows of results: 
{  "type":"set-params",
   "id":"default-params",
   "params": [
      {"key":"fl", "value":"id", "policy":"append"},
      {"key":"rows", "value":"10", "policy":"replace"}
    ],
   "skip":false
}

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Configuration

When entering configuration values in the UI, use unescaped characters, such as \t for the tab character. When entering configuration values in the API, use escaped characters, such as \\t for the tab character.