SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 4)
   ExpressionList (children 3)
    Literal \'(backward, tail, 1)\'
    Identifier id
    Function sequenceNextNode (alias next_node) (children 2)
     ExpressionList (children 3)
      Identifier dt
      Identifier action
      Function equals (children 1)
       ExpressionList (children 2)
        Identifier referrer
        Literal \'1\'
     ExpressionList (children 2)
      Literal \'backward\'
      Literal \'tail\'
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier test_base_condition
   ExpressionList (children 1)
    Identifier id
   ExpressionList (children 1)
    OrderByElement (children 1)
     Identifier id
