CreateQuery tbl (children 3)
 Identifier tbl
 Columns definition (children 1)
  ExpressionList (children 2)
   ColumnDeclaration key (children 1)
    DataType UInt64
   ColumnDeclaration agg (children 1)
    DataType UInt64
 Storage definition (children 2)
  Function MergeTree
  Identifier key
