CreateQuery source (children 3)
 Identifier source
 Columns definition (children 1)
  ExpressionList (children 2)
   ColumnDeclaration ts (children 1)
    DataType DateTime (children 1)
     ExpressionList (children 1)
      Literal \'UTC\'
   ColumnDeclaration n (children 1)
    DataType Int32
 Storage definition (children 3)
  Function MergeTree
  Function toYYYYMM (children 1)
   ExpressionList (children 1)
    Identifier ts
  Function tuple (children 1)
   ExpressionList
