Resources & Cost
Assignment Lag
Assignment lag ≠ relationship lag; Drive Activity Dates is a flag
What a planner means
A resource does not have to start when the activity starts. Planned Lag is the time between the activity’s planned start and that resource’s planned start on the same activity. Zero means they start together.
Oracle: assignment start = activity start plus the lag. The assignment duration can also be shorter than the activity (finish earlier) or longer (finish after the activity). An assignment that finishes after the activity does not by itself hold successors — the activity finish still drives logic — unless Drive Activity Dates is on for that assignment.
This is not TASKPRED lag (FS/SS/FF/SF wait between two activities). See TASKPRED (Activity Relationships) and Calendar Used for Relationship Lag.
Before the activity starts, Remaining Lag equals Planned Lag. After it starts, Remaining Lag is the gap between the activity’s remaining start and the resource’s remaining start.
Apply Actuals honors assignment lag: Oracle’s example is an 18–27 Jun activity, assignment lag +5 days, new Data Date 20 Jun — the activity can take auto-compute progress; the lagged assignment does not yet. See Apply Actuals Posts Progress and Moves the Data Date.
Drive Activity Dates
Oracle: if Drive Activity Dates is selected, recalculating the assignment also changes the activity dates. Several driving assignments plus network logic set the activity. TASKRSRC.rollup_dates_flag is Drive Activity Dates. PROJECT.def_rollup_dates_flag is the default for new assignments.
XER
| Column | Oracle label |
|---|---|
TASKRSRC.target_lag_drtn_hr_cnt | Original Lag |
TASKRSRC.relag_drtn_hr_cnt | Remaining Lag |
TASKRSRC.rollup_dates_flag | Drive Activity Dates |
TASKRSRC.target_start_date / target_end_date | Planned Start / Planned Finish |
TASKRSRC.restart_date / reend_date | Remaining Early Start / Finish |
PROJECT.def_rollup_dates_flag | Drive Activity Dates Default |
Hours (*_hr_cnt). Do not use the MPX map’s lag_drtn_hr_cnt name on a project XER — that token is the MPX assignment field, not the XER column.
Microsoft Project
Assignment Delay is the closest object. Microsoft: Assignment Delay = assignment start − task start (you can type the delay or a later assignment start). Predecessor Lag is a different field (task-to-task). Oracle’s own MPX map sends P6 assignment lag to Assignment Delay. Do not send it to predecessor Lag.
Don't
- Treat assignment lag as relationship lag, or draw it as a link.
- Treat assignment start/finish as the activity bar.
- Treat Drive Activity Dates as always on, or treat
PROJECT.def_rollup_dates_flagas rewriting existing assignments. - Invent
lag_drtn_hr_cnton XER TASKRSRC. - Map assignment lag to MSP predecessor Lag.