Specifying the -zt option sets the RequestTiming property to On. Once request timing is turned on, you can use the sa_performance_diagnostics
system procedure to retrieve all the values of the properties that store request timing information.
The following properties return request timing information only when RequestTiming is turned on. Otherwise the properties
return NULL. All of the properties except for ReqStatus are connection, database, and server properties. The database and
server properties are an aggregation of the connection values since the database or server started, and these database and
server properties only return information if RequestTiming is enabled.