For example I have Documents A, B, C. User 1 must only be able to see Documents A, B. User 2 must only be able to see Document C. Is it possible to do it in SOLR without filteri
You can implement your security model using Solr's PostFilter. For more information see http://searchhub.org/2012/02/22/custom-security-filtering-in-solr/
Note: you should probably cache your access rights otherwise performance will be terrible.