CreateQuery dt64test (children 3)
 Identifier dt64test
 Columns definition (children 1)
  ExpressionList (children 2)
   ColumnDeclaration dt64_column (children 1)
    DataType DateTime64 (children 1)
     ExpressionList (children 1)
      Literal UInt64_3
   ColumnDeclaration dt_column (children 2)
    DataType DateTime
    Function toDateTime (children 1)
     ExpressionList (children 1)
      Identifier dt64_column
 Storage definition (children 3)
  Function MergeTree
  Function toYYYYMM (children 1)
   ExpressionList (children 1)
    Identifier dt64_column
  Identifier dt64_column