SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 3)
    Function empty (children 1)
     ExpressionList (children 1)
      Identifier nest.a
    Function empty (children 1)
     ExpressionList (children 1)
      Identifier nest.b
    Function empty (children 1)
     ExpressionList (children 1)
      Identifier nest.c
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier decimal
