Market Basket-find associate items not on same orders but on same session

[#1]

Help!!

I have the sample data like below, I want to do a basket analysis, e.g. when I select an category on an list box(e.g. DL) the graph would show the associate category that is in the same session id, but without invoice id (in terms of no. of time of session)

Session ID	InvoiceID	ItemID	Category
3620	1	211	DL
3620	1	212	DL
3620	1	213	DB
3620	1	214	DB
3620	1	215	W
3620		216	Q
3620		217	Q
3620		218	E
1111	2	219	DL
1111	2	220	E
1111	2	221	JL
1111		222	JL
1111		223	Q
1111		224	W

for example, when I select DL on a list box,The result should be below, how can I achieve below  with what dimension and expression??? Many Thanks for help.

Category	No. of session
Q	2
E	1
W	1

[#2]

Sunny,

Because i want to know for each category, how many times it have not been sold with the selected category on the same session..in the sample data above, i assume that i would click category E( have been sold on the session) on a list box , and the chart shows that JL have have not been sold with category E in one session( 1111)....

[#3]

i am able to find out the category that have been sold together with the selected category with the below expression with the use of invoice ID, however i cannot find those not sold together with the selected item......

=count(DISTINCT {$<InvoiceID=P({$}InvoiceID),Category=E({$}Category),Flag = {0}>}InvoiceID) 

[#4]

Tried many times, could you kindly help.

[sunny_talwar]

Not 100% sure, but try this

=Count(DISTINCT{<Category = p({<Category, [Session ID] = p([Session ID]), Flag = {1}>}), Flag = {1}, [Session ID] = p({<Flag = {0}>})>}[Session ID])

[#6]

Thanks so much sunny, this is what i want to acheive.

you saved my day.

[sunny_talwar]

Super... I am glad you got what you wanted...

Best,

Sunny