SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Identifier event
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.events
   Function less (children 1)
    ExpressionList (children 2)
     Function length (children 1)
      ExpressionList (children 1)
       Identifier description
     Literal UInt64_10
