CreateQuery aggregating_merge_tree (children 3)
 Identifier aggregating_merge_tree
 Columns definition (children 1)
  ExpressionList (children 3)
   ColumnDeclaration key (children 1)
    DataType UInt32
   ColumnDeclaration val (children 1)
    DataType SimpleAggregateFunction (children 1)
     ExpressionList (children 2)
      Identifier max
      DataType UInt32
   ColumnDeclaration date (children 1)
    DataType Datetime
 Storage definition (children 3)
  Function AggregatingMergeTree (children 1)
   ExpressionList
  Identifier date
  Identifier key
