CreateQuery order_by_nulls_first (children 3)
 Identifier order_by_nulls_first
 Columns definition (children 1)
  ExpressionList (children 2)
   ColumnDeclaration diff (children 1)
    DataType Nullable (children 1)
     ExpressionList (children 1)
      DataType Int16
   ColumnDeclaration traf (children 1)
    DataType UInt64
 Storage definition (children 2)
  Function MergeTree
  Function tuple (children 1)
   ExpressionList
