Help with record selection/grouping

Question

I am trying to create a report as follows, but am running into some problems with my selection/grouping:
Data Structure (each line is a separate record; each employee has 2 records)
Employee             TaskID      TaskStatus           Marker         Date Modified
1                               A                CLOSED             x
1                               B                OPEN                  N/A
2                               A                CLOSED              y
2                               B                OPEN                 N/A
3                               A                CLOSED             x
3                               B                CLOSED            N/A
4                               A                CLOSED             y
4                               B                CLOSED           N/A
Report Requirements
I want a report that displays only employee number and the date that Task B was completed for all employees, and I want these records grouped based on Task B's Task Status (no problem.  I did this).
However, I want to sub-group these Task B records (within Task Status) by the Marker field for Task A records!  (I can't figure this out?  If I only pull in Task B records, how can I compare what the associated employee has as a marker for their Task A record?)
Again, I only want to display data from the employee's Task B record, while subgrouping on a field value from the empoyee's Task A record.  The report would be structured as follows:
Task B (OPEN), with Task A - Marker (x)
                 {Date Modified}
Task B (OPEN), with Task A - Marker (y)
                 {Date Modified}
Task B (CLOSED), with Task A - Marker (x)
                {Date Modified}
Task B (CLOSED), with Task A - Marker (y)
                  {Date Modified}
Thanks.
Gary

Answer 1

The easiest way would be to use an SQL Command that returns both the Task A and Task B data on one record.  Something like (MS SQL):
select b.employee, b.taskid as task_b, b.task_status_b, b.marker as marker_b, b.date_modified as date_modified_b,
    a.taskid as task_a, a.task_status_a, a.marker as marker_a, a.date_modified as date_modified_a
from table a, table b
where a.employee = b.employee
and a.taskid = 'A'
and b.taskid = 'B'
HTH,
Carl