cascade_delete_def cascade_update_def(?)
{ $return = { on_delete => $item[1], on_update => $item[2][0] } }
-cascade_delete_def : /on\s+delete\s+(\w+)/i
+cascade_delete_def : /on\s+delete\s+(set null|set default|cascade|restrict|no action)/i
{ $return = $1}
-cascade_update_def : /on\s+update\s+(\w+)/i
+cascade_update_def : /on\s+update\s+(set null|set default|cascade|restrict|no action)/i
{ $return = $1}
table_name : qualified_name