SRU::Request::SearchRetrieve - A class for representing SRU searchRetrieve requests

    ## creating a new request
    my $request = SRU::Request::SearchRetrieve->new(
        version => '1.1',
        query   => 'kirk and spock' );

The constructor which you can pass the following parameters: version, query, startRecord, maximumRecords, recordPacking, recordSchema, recordXPath, resultSetTTL, sortKeys, stylesheet, extraRequestData. The version and query parameters are mandatory.

Fetch the root node of the CQL parse tree for the query.