http://developers.de/blogs/damir_dobric/archive/2008/08/10/entity-framework-compiling-error.aspxError 67 Error 3026: Problem in Mapping Fragment(s) starting at line(s) (982, 1103, 1112, 1121, 1129): Data loss or key constraint violation is possible in table TAggregationEvent. The following C-side state is not preserved upon retrieving persistedenCommunityServer 2008 SP1 (Build: 30619.63)