> ok. But do we need it? Thats what I am confused at. should 1 key from > table_1 pull all the data in relationship as they were inserted?
Suoplementing all the great info Jack has relayed: For the unique key in schema.xml, you really only need to be concerned about the document uniqueness within Solr, not the database. Are the entries from table 2 (and table 3, etc) full siblings to the entries in table 1? If they are, and you can't guarantee they will have different ID values from table 1, then you need some kind of composite key. If tables 2 and 3 are used to populate data in documents from table 1, then you don't need to worry about their unique keys in Solr. Solr already has enough information to uniquely id any of the top level docs. Thanks, Shawn
