Hidden and purged tracks
Track Manager allows you to focus your analysis by giving you two different methods for reducing the amount of tracking data on your screen: hiding and purging tracks.
Hiding tracks
Hiding tracks can be useful if you have a lot of tracks on your map and you are doing analysis that doesn't require viewing all of them. Tracks that are not needed can be hidden from view to get rid of clutter on your map, and they will remain hidden until you decide to make them visible again.
To hide tracks, activate the set of tracks you want to hide and click the Hide Track button. Track Manager maintains a list of all the tracks you have chosen to hide, and the tracks become labeled as "hidden" in the track list. The Filter By Category options above the track list can be used to focus your analysis by only listing visible tracks in your track list. Alternatively, they can also be used to obtain a complete list of all the tracks that are currently hidden.
When you want to make the tracks visible again, activate them and click Show Track. If you want to make sure that all the tracks in your map become visible again, you can use the All button to select all tracks before clicking the Show Track button.
Purging tracks
Track-based purging is only available for real-time tracking layers. It is an advanced option for managing real-time tracking data, and it is intended to be used in addition to the service-based purging that is typically in place for all tracking layers. The most common way to purge tracking services is to delete the oldest data when the feature count exceeds a configured amount.
Learn more about service-based purging
Service-based purging treats all tracks the same, but many Tracking Analyst users are performing focused analysis that doesn't involve all the tracks in a tracking layer. Choosing to purge individual tracks that are not needed allows more system memory to be dedicated to storing data from tracks that are of interest. When the tracks being purged are needed again, you can stop purging them.
When you choose to purge individual real-time tracks, all the features contained in the track are deleted. In addition, the system continues to purge any new features received that belong to that track. Therefore, purging a track is a continuous process that continues to work until you turn it off. When you stop purging the track, features belonging to it are allowed to flow into the tracking layer again, similar to opening a valve and allowing water to flow again.
When you choose to purge a track or a set of tracks, all the corresponding features up to the current time are permanently deleted. Therefore, you should be very careful when purging tracks.
Purging tracks works the same way as hiding tracks. Activate the set of tracks you want to purge and click the Purge Track button. Track Manager maintains a list of all the tracks that are currently being purged, and the tracks become labeled as "purged" in the track list. The Filter By Category options can be used to obtain a complete list of all the tracks that are currently being purged.
When you want to stop purging tracks, activate them and click Stop Purging. If you want to make sure that you are no longer purging tracks, you can use the All button to select all tracks before clicking the Stop Purging button.
Purging and hiding tracks
When working with real-time tracking layers, it is important to note that you can purge and hide tracks at the same time. If this happens, the track's label will reflect this by saying "hidden/purged." If you stop purging the track, it will still be hidden from view. Of course, any track that is being purged will be hidden from view, regardless of whether you have chosen to hide it.
The list of tracks that are currently being purged is maintained separately from the list of tracks that are being hidden. This allows you to add and remove both conditions independently, using whichever methods you choose, which can be very helpful if you are using both data reduction options with a lot of real-time tracks.