Explain EXPLAIN ESTIMATE (children 1)
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 3)
    ExpressionList (children 1)
     Function count (children 1)
      ExpressionList
    TablesInSelectQuery (children 1)
     TablesInSelectQueryElement (children 1)
      TableExpression (children 1)
       TableIdentifier test.hits
    Function less (children 1)
     ExpressionList (children 2)
      Identifier CounterID
      Literal UInt64_29103473