SelectWithUnionQuery (children 2)
 ExpressionList (children 1)
  SelectQuery (children 4)
   ExpressionList (children 3)
    Identifier CurrentMetric_TemporaryFilesForAggregation
    Identifier CurrentMetric_TemporaryFilesForJoin
    Identifier CurrentMetric_TemporaryFilesForSort
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.metric_log
   ExpressionList (children 1)
    OrderByElement (children 1)
     Identifier event_time
   Literal UInt64_5
 Identifier Null
