Yes, you can display # days, # hours, # minutes, and # seconds.  You will need to create several calculations.

Step 1:

1. Hold Time Diff: this is a level of detail (your group by in SQL)

{FIXED [id], [category], [dates]: SUM(DATEDIFF(‘second’,[Start Date], [End Date])}

Step 2 -6:

Create Hold Days, Hold Hours, Hold Minutes, Hold Seconds, which we will use to display hold days, but more importantly, show hours/mins/sec when the hold is on the same day, which will show "0" under 'Hold Time Days' (see calc below)

2. Hold Days:

(SUM([Hold Time Diff]) - (SUM([Hold Time Diff])%(24*3600)))/(24*3600)

3. Hold Hours:

(((SUM([Hold Time Diff])%(24*3600))) - (SUM([Hold Time Diff])%(24*3600))%3600)/3600

4. Hold Minutes

(((SUM([Hold Time Diff])%(24*3600))%3600) - ((SUM([Hold Time Diff])%(24*3600))%3600)%60)/60

5. Hold Seconds

IF INT(SUM([Hold Time Diff]) %3600 %60) < 10 THEN "0" ELSE "" END + STR(INT(SUM([Hold Time Diff]) %3600 %60))

Step 6 – Combine the above Holds for Days, Hours, Minutes, and Seconds to create a readable Hold Duration field.

6. Hold Duration:

IF [Hold Days] > 0 THEN

STR([Hold Days])+" Day"+" "+

STR([Hold Hours])+" Hr"+" "+

STR([Hold Minutes])+" Min"+" "+

STR([Hold Seconds])+" Sec"

ELSE

STR([Hold Hours])+" Hr"+" "+

STR([Hold Minutes])+" Min"+" "+

STR([Hold Seconds])+" Sec"

END

Happy Tableau-ing!