how to get count of a data

[Sara_3]

Hi,

I am creating the sample data table  here :

Code	Category	Key
112	A	001236
112	A	002589
112	A	002574
456	B	003698
456	B	007896
890	A	002365
890	A	005987
890	A	002365
342	B	001478

.i have 3 fields i want count of "key" of all code where "category" = A. I tried aggr function in expression but did not to get the expected answer. 

my input is Code. for example: when I select code (112 ) it belongs to category A . so my expected answer is count of all key which has category A. 

Expected result:      A =  count key = " 6 "

i have tried this expression but it gives me different answer.

Sum(Aggr(Count(Key),category)

Thanks!

[Mark_Winter]

Hi Sara,

count({<category={'A'}>}key)

[Sara_3]

Hi , sorry i forgot to mention that my input is Code. for example: when I select code (112 ) it belongs to category A . so my expected answer is count of all key which has category A. 

[Sara_3]

i tried this expression but it gives me different answer.

Sum(Aggr(Count(Key),category)

[Mark_Winter]

Aggr({1}nodistinct Count(key),category)

[Sara_3]

Thanks Mark , but does not work . it gave me total count of all key.