The number of different query parsers in Solr was always an amusement for me. Can someone here say how many of them are currently available and say what are those? Anyway, in this entry we won’t be talking about all the query parsers available in Solr, but we will take a quick look at one of them – the SwitchQueryParser introduced in Solr 4.2.
With the release of Solr 4.2 we’ve got the possibility to use the HTTP protocol to get information about Solr index structure. Of course, if one wanted to do that prior to Solr 4.2 it could be achieved by fetching the schema.xml file, parsing it and then getting the needed information. However when Solr 4.2 was released we’ve got a dedicated API which can return the information we need without the need of parsing the whole schema.xml file.