SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Function CAST (alias x) (children 1)
     ExpressionList (children 2)
      Function arrayJoin (children 1)
       ExpressionList (children 1)
        Literal Array_[\'Hello\', \'world\']
      Literal \'Enum(\\\'Hello\\\', \\\'world\\\')\'
   ExpressionList (children 2)
    Identifier x
    Function transform (children 1)
     ExpressionList (children 4)
      Identifier x
      Literal Array_[\'Hello\', \'world\']
      Literal Array_[UInt64_123, UInt64_456]
      Literal UInt64_0
