Mittwoch, 8. September 2010 07:51Moderator
I have just seen a difference in behaviour of Hammock tasks between 2007 and 2010 when changing assignment units or work, if a ressource is assigned to the task. In 2007 Start and Finish was kept as defined by "Paste special". In 2010 duration and start/finish is changed, ignoring dates of "Paste special". Has someone else seen that behaviour?
Mittwoch, 8. September 2010 08:04Moderator
I see the same behavior in my tests. I've set the Start and Finish date of a task using Paste Links. Modifying the Work does change Start and/or Finish date of the task.
Recalculating the project does not make a difference. But if I modify start/finish of one of the tasks between which this task is a hammock task, the Paste Links are recalculated as expected.
Maybe this is by design? Allowing you to override the Paste Link?
My EPM blog: Projectopolis
Mittwoch, 8. September 2010 08:16Moderator
thanks for confirmation. I found the same workaround. But I don't like it. You have to pay a lot attention if you are changing your tasks, since the indicator is quite small (of course you can add column "Linked fields"). I hope it is not by design and will be changed back by any update in future?
Mittwoch, 8. September 2010 09:18Moderator
Whilst admitting that the behaviour is not logical, giving a Hammock task a type other than Fixed Duration isn't either, and with Fixed Duration as type changing resource units doesn't change duration or dates.
And BTW, Help on Hammock tasks I read a few years ago read that one should never assign resources to Hammock tasks...
Mittwoch, 6. Oktober 2010 06:16Moderator
sorry for my late answer - I thought I had replied immediately.
From my understanding a Hammock task is not a task with Fixed Duration. If it was, I could put in a duration. It can be fixed units (the way I use it in general) or fixed work. Moreover, these are the only two task types Hammock is working with, also in 2007. If you set a task to fixed duration, links will be ignored completely in 2007 and 2010.
I have never read about never assigning resources on Hammock tasks. Would be interesting, if that is still valid for 2010? We use it mainly for a task "Project Management", working with Project Server. So we have to deal with enterprise resource planning and time reporting on a daily basis.
Mittwoch, 6. Oktober 2010 09:12Moderator
Finally, I will stop thinking about hammock tasks. What is it exactly people want? I thought it was by definition a task of which start and finish were defined by dates from other tasks. If that is so, one should not enter any object that may change that. Now you tell me you want to respect links???
I can't fiind back the article saying you should not put resources on hammock tasks (although it seems wise) - may be deleted, but I DID find back the article saying you shouldn't put predecessors before hammock tasks (141733).
Anyway, Hammock tasks react exactly as if you enter manually Start and Finish for the task, ending up with either a start no earlier than or a Finish no earlier than constraint, no more, no less - and when you change units for a fixed units or a fixed work task duration will change and the result will be depending on the constraint type. I don't see how one could avoid that.
Mittwoch, 6. Oktober 2010 10:21Moderator
The reason for using Hammock tasks can be to have a task over the whole duration of a project. If duration increases, this task duration should also increase. So taking the project start milestone as start date for this task and the task finish milestone as finish date of this task, does exactly what is needed e.g. for a Project Management task.
But my initial question was regarding a difference in behaviour. I think I know what I can do with Hammock Tasks, and what are the limits. So I have no need to discuss Hammock task in general. I am only interested in a change from 2007 to 2010:
Milestone A: 11\1\2010
Milestone B: 11\30\2010
Two tasks: PM1 with Fixed Units, PM2 with Fixed Work. Both hammock tasks with start date from Milestone A, finish dated linked to Milestone B.
One resource assigned with 10%.
Changing work to 10hrs:
In 2007, assignment units are changed accordingly. Start and finish date links are kept, so still 11/1/2010-11/30/2010 - great!
In 2010, assignment units are kept, but start date is moved to 11/12/2010. So my link to Milestone A is ignored. That's not what I expect of a Hammock task! No difference caused by task type.
Changing assignment Units to 5%:
In 2007, work ischanged accordingly. Start and finish date links are kept, so still 11/1/2010-11/30/2010 - great!
In 2010, work iskept, but start date is moved to 9/27/2010. So my link to Milestone A is ignored. That's not what I expect of a Hammock task! No difference caused by task type.
Hans verified my observation, I have verified in serveral environments in the meantime.
So my summary is that it has changed in 2010 and I have to live with it (until perhaps MS will change it back to 2007 behaviour).
Thanks for your support!
Mittwoch, 6. Oktober 2010 10:27Moderator
thanks for searching the article to avoid assignments on Hammock tasks. As I wrote, I have never read something like that, but I will keep my eyes open. So far I haven't seen any issues caused by that, supporting several customers who like Hammock tasks.
I am aware of the fact, that you can't use pre- or successors with Hommock tasks. If you do so, it is really funny to look at ;-)