SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Function greater (children 1)
     ExpressionList (children 2)
      Identifier value
      Literal UInt64_0
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.histogram_metrics
   Function and (children 1)
    ExpressionList (children 2)
     Function equals (children 1)
      ExpressionList (children 2)
       Identifier name
       Literal \'keeper_client_queue_duration_milliseconds\'
     Function equals (children 1)
      ExpressionList (children 2)
       Function arrayElement (children 1)
        ExpressionList (children 2)
         Identifier labels
         Literal \'le\'
       Literal \'+Inf\'
