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I have seen in ClearCase that there is a Snapshot view and a Dynamic view. What are the differences between these types of views (I'm assuming there are only two types of views) and when are the appropriate times to use them?

brainimus
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  • I found a good article explaining these views: [wiki IBM Rational ClearCase](http://en.wikipedia.org/wiki/IBM_Rational_ClearCase#Views) – Joelmob May 27 '10 at 18:23

1 Answers1

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Snapshot views are based on the local filesystem (like a workspace in Subversion):

  • you load files anywhere you want on your hard drive
  • you have to 'cleartool update' to refresh its content

Dynamic views are based on network content: they represent the dynamic (as in "always refreshed") view of a network content (the remote VOB versions selected by the config spec)

  • you access them only through the "dynamic view" mount point (M:\ on Windows or /view on Unix: it is a MVFS mount point: MultiVersion Filesystem)
  • you don't have to refresh them

See the second part of this SO answer for a discussion on when to use dynamic views vs. snapshot.

I often use them (the dynamic views) in addition of snapshot views, meaning it is a great tool to just "see" the files (you can for example use a dynamic view to tweak its config spec until you see what you want and then copy those select rules into your usual snapshot view)

Community
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VonC
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  • @Paulus yes, I mention speed (access speed to read data) in the second part of http://stackoverflow.com/a/1074785/6309 – VonC Aug 27 '14 at 10:36
  • Another aspect: speed. Dynamic views are great for quickly testing config specs, but accessing many files from the dynamic view is slow. And if you are trying to access them via ssh for rsync for example you run into many permission and other problems. Snapshot views can take a few minutes to update (for about a 15k file project), but once updated they are on the local filesystem and you have much faster and well defined (permissions etc) access to them. – Paulus Aug 27 '14 at 10:42
  • @Paulus indeed. The last sections of http://stackoverflow.com/a/1074785/6309 illustrate your point. – VonC Aug 27 '14 at 10:44