CreateQuery tnul (children 3)
 Identifier tnul
 Columns definition (children 1)
  ExpressionList (children 1)
   ColumnDeclaration lc (children 1)
    DataType Nullable (children 1)
     ExpressionList (children 1)
      DataType String
 Storage definition (children 2)
  Function MergeTree
  Function tuple (children 1)
   ExpressionList
