SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 2)
    Function if (alias a) (children 1)
     ExpressionList (children 3)
      Function and (children 1)
       ExpressionList (children 2)
        Literal UInt64_0
        Identifier id
      Literal UInt64_1
      Literal UInt64_2
    Function sum (children 1)
     ExpressionList (children 1)
      Identifier id
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Subquery (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 1)
          ExpressionList (children 1)
           Literal UInt64_1 (alias id)
   ExpressionList (children 1)
    Identifier a
