SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 3)
    QualifiedAsterisk (children 1)
     Identifier left_table
    QualifiedAsterisk (children 1)
     Identifier middle_table
    QualifiedAsterisk (children 1)
     Identifier right_table
   TablesInSelectQuery (children 3)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier left_table
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      TableIdentifier middle_table
     TableJoin (children 1)
      Function equals (children 1)
       ExpressionList (children 2)
        Identifier left_table.id
        Identifier middle_table.id
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      TableIdentifier right_table
     TableJoin (children 1)
      Function equals (children 1)
       ExpressionList (children 2)
        Identifier middle_table.id
        Identifier right_table.id
   ExpressionList (children 4)
    OrderByElement (children 1)
     Identifier left_table.id
    OrderByElement (children 1)
     Identifier val_left
    OrderByElement (children 1)
     Identifier val_middle
    OrderByElement (children 1)
     Identifier val_right