OK this seems to be a little complicated and confusing.

I have a base table 

```
Schedule
(
    RowID, 
    ScheduleName, 
    ScheduleColumn1, 
    ScheduleColumn2, 
    ScheduleColumn3
)

```

I have a separate application that imports records to another table 

```
ImportSchedule
(
    RowID, 
    ScheduleName,
    ScheduleColumn1, 
    ScheduleColumn2,  
    ScheduleColumn3 
)

```

Now I need to join the 2 tables and display records that do no match. Basically if table `ImportSchedules` does not have matching records on columns `ScheduleColumn1`, `ScheduleColumn2`, `ScheduleColumn3` with table `Schedule`.

This is easy with the help of left join on all the above three columns. 

The difficult part is finding which column does not match and list it as a failure reason.