Utilization Tips for Viewpoint Rewind

Blog
The best minds from Teradata, our partners, and customers blog about whatever takes their fancy.
Teradata Employee

This blog discusses tips, tricks, and use cases for Teradata Viewpoint's "Rewind" feature. Hopefully this blog will give you some new ideas on more efficient navigation and different ways of utilizing rewind that you may have overlooked in the past.  

If you have been using single clicks with the rewind feature navigation buttons (seconds, minutes, hours) to move back in time, then you are creating longer clickstreams than necessary! Here are some tips for faster time travel. For rapid progression on hours, minutes, or seconds one can drag and hold the slider over the appropriate navigation button (the arrow buttons) to simulate multiple clicks. For instance to traverse rewind back several hours, you could drag and hold as shown below:

Another somewhat hidden feature is the ability to navigate in increments. This is done by clicking between navigation buttons to step back in different increments. For instance, a single click between the seconds and minutes buttons, traverses back 10 seconds. Similarly a single click between minutes and hours will traverse in 10 minute increments while between the hours button and time display, single days. Hovering over these areas will display pop-up help to show what options are available. Some of those available options are shown below:

Lastly for navigation, you can always manually enter a specific date or time as well as just picking another day in the pop-up monthly calendar. Hopefully these navigation tips will help with utilizing the rewind feature more effectively. 

Next let's look at some interesting use cases for the rewind feature that may have you think about it differently going forward. Viewpoint's rewind is certainly an awesome tool for debugging past events but it can be used as a filter or comparison analysis tool as discussed below. Some portlets in Viewpoint offer time filtering for durations like last hour or last day. What some don't realize is those don't have to only be the last hour or day from current time but can be any hour or any day based on the rewind setting.

For example, a customer wants to see the alerts triggered between the hour of midnight and 1:00AM earlier today. They bring up the Alert Viewer portlet which allows selections of "Last 1 Hour" or "Last 1 Day" maybe leading someone to think they have to bring up a full day's alerts to see that one hour increment of midnight to 1:00AM. A more efficient approach would be to open rewind and set it to 1:00AM and then select the "Last 1 Hour" option to view only those alerts in that hour. This is how one can use rewind as a filter for portlets as shown here.

Another use case for the rewind feature can be as a comparison tool enabled by the portlet rewind control pull down. Using this menu, one can compare present to past or multiple times in the past. Below is showing a comparison of past with present for queries that were running at the same time last week. The Query Monitor portlet on the right has been "unlinked" from rewind so is displaying the current time. Note the red slash through the rewind indicator. The Query Monitor portlet on the left shows the pull down to accomplish this.

Similarly, if you want to compare multiple times in the past, you would rewind to the first time and pause one of the portlet instances there and then continue to rewind to the other time for comparison. One portlet follows while the other one that is paused does not. 

Hopefully this has provided some new insights into other use cases for Viewpoint "Rewind"!

 

12 Comments
Enthusiast
Great point on comparision using rewind option. I used to think about the exact purpose of Unlinking a Porlet From Rewind. Now i found the worth reason to have that option. Thanks Gary.
By the way what is this mini opera posted by afishared!, its showing something in different language(i dont know)
Teradata Employee
I'm glad the blog has you thinking about other possibilities with Rewind. That was the intent and was spawned through another customer conversation about how best to navigate where they didn't know about clicking between navigation buttons or holding the slider. The opera thing was spam which has now been addressed.
Enthusiast
Is there a way to get Rewind to use/accept a 24 hour time entry instead of a 12 hour timestamp? I stumbled across the slider just the other week. This is certainly helpful! Thank you.
Teradata Employee
So instead of 11:00 PM, you want 23:00? What would be the use case or is this more of just a preference?
Enthusiast
Right. When entering a point in time into rewind it would be nice to be able to use 23:00 instead of 11:00 PM.

Maybe a global user preference on time in Viewpoint being 12H or 24H time. (Scope creep! LOL)
Teradata Employee
Is there a certain use case for the full 24HR clock? Or just a preference for a user?
Enthusiast
I would like to just comment on a couple of parts of rewind that I find absolutely amazing. I can go back in time and look at blocking queries and even pull up the SQL from both queries and also go back in time and actually step through the explain plan of a problem query after the event - WOW !!!!!! No extra space required on the Datawarehouse system to hold the explains, so now no real need to capture explains in the DBQL.
Teradata Employee
Glad you have found some gems with utilization of Viewpoint's rewind although I want to be sure folks understand that the Viewpoint repository should not be considered a replacement for the Database Query Log (DBQL). Viewpoint's sampling collection strategy won't have the level of detail that DBQL offers so there may be times where you want to get that nth level of information from DBQL. However you certainly need to access DBQL much less than in the past and in particular for analysis of past events utilizing Rewind or the "Query Spotlight" portlet.
This feature is a really amazing and would help DBAs a lot to analyze the issues. Great work team and thanks a ton!!!
Teradata Employee
You're welcome! :-)
Enthusiast

Hi Gary,

We are having an issue with Rewind timestamp with Query Monitor Portlet time stamp. Actually, during one particualr period we are seeing discrepancy between Rewind timestamp and Query Monitor Portlet time. Ex: Rewind timestamp: 9.30 AM but Query Monitor Portlet timestamp: 7.46am and it is fixed timestamp showing until 10.30 am of rewind. It is specific to Query Monitor Portlet with Rewind only but with Metric Analysis, and other portlets are working as expected with Rewind. 

As per my analysis, i find couple of JAVA exceptions in catalina.out but other than that i didn't find any abnormal ones in viewpoint.log, dcs.log, error.log.

At this point , i am thinking to restart the services but before that Is there any specific service or propertices to check related to Query Monitor to refresh this portlet.

Thanks in advance.

Teradata Employee

The time stamp of a portlet can differ from the rewind time as the portlet time is reflecting the last data collection time of the data being displayed. It sounds like the session collector that feeds Query Monitor was not collecting for that period of time and thus why you are seeing the gap.