SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 12)
    Function toNullable (alias a) (children 1)
     ExpressionList (children 1)
      Literal NULL
    Function toNullable (alias b) (children 1)
     ExpressionList (children 1)
      Literal \'Hello\'
    Function toNullable (alias c) (children 1)
     ExpressionList (children 1)
      Function toNullable (children 1)
       ExpressionList (children 1)
        Literal UInt64_1
    Function toNullable (alias d) (children 1)
     ExpressionList (children 1)
      Function materialize (children 1)
       ExpressionList (children 1)
        Literal NULL
    Function toNullable (alias e) (children 1)
     ExpressionList (children 1)
      Function materialize (children 1)
       ExpressionList (children 1)
        Literal \'Hello\'
    Function toNullable (alias f) (children 1)
     ExpressionList (children 1)
      Function toNullable (children 1)
       ExpressionList (children 1)
        Function materialize (children 1)
         ExpressionList (children 1)
          Literal UInt64_1
    Function toTypeName (children 1)
     ExpressionList (children 1)
      Identifier a
    Function toTypeName (children 1)
     ExpressionList (children 1)
      Identifier b
    Function toTypeName (children 1)
     ExpressionList (children 1)
      Identifier c
    Function toTypeName (children 1)
     ExpressionList (children 1)
      Identifier d
    Function toTypeName (children 1)
     ExpressionList (children 1)
      Identifier e
    Function toTypeName (children 1)
     ExpressionList (children 1)
      Identifier f