diff --git a/tools/prune-trace/Pruner.cc b/tools/prune-trace/Pruner.cc
index 1a8ad17e..9c981834 100644
--- a/tools/prune-trace/Pruner.cc
+++ b/tools/prune-trace/Pruner.cc
@@ -70,7 +70,7 @@ bool Pruner::create_database() {
 	    "  data_address    int(10) unsigned NOT NULL,"
 	    "  fspmethod_id    int(11) NOT NULL,"
 	    "  pilot_id        int(11) NOT NULL,"
-	    "  PRIMARY KEY (variant_id, data_address, instr2, fspmethod_id, pilot_id),"
+	    "  PRIMARY KEY (variant_id, data_address, instr2, fspmethod_id),"
 	    "  KEY joinresults (pilot_id,fspmethod_id)) engine=MyISAM";
 
 	return db->query(create_statement.c_str());