how to add a new parameter to solr request

Hello every body I want to modify a little bit the behaviour of Solr and I want to know if it is possible; Here is my problem : I give to Solr document to index which UniqueKey Field is based on the Url and the Time at which the croawler downloaded it so UniqueKey is a digit obtained like

Re: how to add a new parameter to solr request

hello every body I want just to add this example to be more clear. I have this result from solr. result name=response numFound=7 start=0 maxScore=0.59129626 − doc str name=id1/str str name=DocUrlhttp://www.sarkozy.fr/str str name=date01/01/2008/str /doc − doc str name=id2/str str