Forum Discussion
Time Difference Between two resources
Hi Kumar11109,
I had a test about 500k. It was very slow. I think the main cause is that we put a complicated formula on a large dataset. Let's split the formula into two parts as calculated columns.
NextStartTime =
CALCULATE (
MIN ( Table1[Start Time] ),
FILTER (
Table1,
Table1[Session ID] = EARLIER ( Table1[Session ID] )
&& Table1[Index]
= EARLIER ( Table1[Index] ) + 1
)
)TimeSpent = IF ( ISBLANK ( [NextStartTime] ), BLANK (), [NextStartTime] - Table1[End Time] )
Best Regards!
Dale
HI v-jiascu-msft Dale,
I tried using your formula for that you provided me, but this time what happened was that it only calculated the next time for only 1 resource of a session and because of this it only calculated the idle time between for only those resources. I am attaching an image for the same. Also, the formula that you had shared, it was slightly different from the one you had shared earlier.
NextStartTime = CALCULATE ( MIN ( Table1[Start Time] ), FILTER ( Table1, Table1[Session ID] = EARLIER ( Table1[Session ID] ) && Table1[Index] = EARLIER ( Table1[Index] ) + 1 ) )
TimeSpent = IF ( ISBLANK ( [NextStartTime] ), BLANK (), [NextStartTime] - Table1[End Time] )
I tried doing it with the old formula, only separating the time spent and next time and didn't work again.
NextStartTime = CALCULATE ( MIN ( Table1[Start Time] ), FILTER ( Table1, Table1[Index] >= EARLIER ( Table1[Index] ) + 1 && Table1[Session ID] = EARLIER ( Table1[Session ID] ) ))
TimeSpent = IF ( ISBLANK ( NextStartTime ), BLANK (), NextStartTime - Table1[End Time] )
Can we further break down formula? Also, can you explain me the formula?
Thank You,
Kumar Ashwarya
Hi Kumar,
There is two preconditions that we evalute the time spent in one session and the data has orders. Have look at the picture. Let's take session 1 and 2 as example. Time Spent = [the next start time] - [the end time]. The "Time Spent" from session 1 to 2 will be empty. (row 5)
In your latest post, you order the table by "resourceid", so it looks strange. Please reorder it as the orginal one (like below). It's clear there is three moves in session 1 and there will be three "time spent".
I split one formula into two to get high performance.
Best Regards!
Dale
I did not sort it this time, but its still working the same way.
Look at the formula that I have applied, I hope it's not incorrect.
Hi Kumar,
You can see the index is disordered. That's why the result is wrong. If we don't use an index, the performance will be terrible due to we have to filter and compare. Let's add a useful index.
1. Open "Query Editor", select "Session ID", sort a->z;
2. Click to open "Advanced Editor", add ", {"Start Time", Order.Ascending}" as the picture showed;
3. Click "Done", we will see an arrow in "session ID" and an arrow in "Start Time";
4. Add index now.
Why we do this? There is an order along time when people move from one resource to another in one session. If this is true, it would work. We can use (index + 1) to get the next "Start Time" without comparing many "Start Time" to get the most recent "Start Time", which is consuming performance.
Best Regards!
Dale