diff --git a/xCAT-server/lib/xcat/schema/samples/Sample.pm b/xCAT-server/lib/xcat/schema/samples/Sample.pm
index 41defe3ca..77804f164 100644
--- a/xCAT-server/lib/xcat/schema/samples/Sample.pm
+++ b/xCAT-server/lib/xcat/schema/samples/Sample.pm
@@ -51,7 +51,6 @@ package xCAT_schema::Sample;
     x_llnode => {     
         cols => [qw(node jobid jobstatus cpu_usage comments disable)],
         keys => [qw(node)],
-        foreignkeys => [qw(("node") REFERENCES x_lljob("node") ON DELETE CASCADE)],  # double quote are for db2,  use backtics for mysql, noquotes for postgresal and sqlite. Tables with a Foreign key must not point to tables with a Foreign key  or the tables may not be created in the correct order. Only one Foreign key per table is supported.  
         required => [qw(node jobid)],
         types => {
 	    jobid => 'INTEGER',