Scheduling and Constraints
As the predecessor activities of the LOE are statuses with actual dates, the LOE itself will automatically inherit the earliest of these dates for its actual start date. As the data date is moved, and based on the balance of activities' cumulative remaining duration within the context of the LOE, P6 will adjust the progress accordingly. As the last successor to the LOE activity is "statused", P6 will automatically use the latest successor date for the LOE Actual Finish.
WBS Summary activity is a type of activity that is rarely used but can be powerful when needed. The WBS Summary requires no relationships because it inherits its dates from all other activities within the same WBS component when the schedule is calculated (F9). This is useful when the project activities are more detailed than the level at which actuals or costs are reported and collected. For example, if the timesheets in use at your organization are not a part of the Primavera system and if time is input by cost account or by scope item rather than each activity in the schedule, then it makes sense to use WBS Summary activity when reporting against timesheets. Another frequent use of the WBS Summary is to cost load the schedule at the deliverable level rather than at the activity or commodity level, which is more granular in nature.
For WBS Summary Activities, the assignments, planned units, and other data are input to the activities, but the actual units and actual costs are input to the WBS Summary activity for that WBS component. The WBS summary activity uses the earliest early start among the activities and the latest late finish as its start and finish. Its duration is derived as the longest path among its fellow activities within the same WBS component.
Just as with LOE activity types, the WBS Summary will inherit the earliest actual start and the latest actual finish from the activities within its WBS group. If there is a remaining duration for activities within the WBS group, then the progress for the WBS Summary is based on the duration between the actual start, the data date, and the latest finish date.
|activity in the description field. There are no other visual indicators|
|that this is a WBS Summary type unless you look at the General tab|
Task Dependent is the most common type of activity. Using this duration type, a Task Dependent activity will calculate its start as the next unit of time after the currently scheduled finish date of its predecessor in the logical sequence that is created by its relationships. If activity A has a calculated finish date of end of working time as Tuesday, then activity B will start at the beginning of working time Wednesday. But this will depend upon each item in this table (assigned resource or role, calendars, settings, constraints, and so on).