CreateQuery data (children 3)
 Identifier data
 Columns definition (children 1)
  ExpressionList (children 3)
   ColumnDeclaration key (children 1)
    DataType Int
   ColumnDeclaration legacy_features_Map.id (children 1)
    DataType Array (children 1)
     ExpressionList (children 1)
      DataType UInt8
   ColumnDeclaration legacy_features_Map.count (children 1)
    DataType Array (children 1)
     ExpressionList (children 1)
      DataType UInt32
 Storage definition (children 3)
  Function MergeTree (children 1)
   ExpressionList
  Identifier key
  Set
