SSAS : Filter Cube - ssas

I have dimension and fact table. The dimension is PATIENTDBOID meanwhile the fact table is Total_Admissions.
Now, I want to filter for Patient that Admission >1
Can someone help me how. ?

You Can use Filter Function to Apply filter on Measures with Logical Expression.
Since I don't know Exact Dimension Name, You can try something like below.
0 - Represents COLUMNS
1 - Represents Rows
SELECT [Measures].[Total_Admissions] ON 0,
FILTER(
[Patient].[Patient].[PatientDBOID].MEMBERS
, [Measures].[Total_Admissions]>1)
ON 1
FROM [Cube Name]

Related

MDX where clause in subquery does not slice cube - how to understand?

This query gives me sales of one store:
select
[measures].[sales] on 0
from [MyCube]
where [store].[store].[042]
However, if I move the slicer to inside of the subquery, it gives me sales of all stores.
select
[measures].[sales] on 0
from (select
from [MyCube]
where [store].[store].[042]
)
How to understand the mechanisms behind this difference?
This is also noted in this article, but without much explanation.
----EDIT----:
I tried various things and read around for a while. I'd like to add a question: is there a scenario in which the where clause in sub-select does filter the result?
This query gives me sales of all stores in state MI (store [042] belongs to MI):
select
[measures].[sales] on 0
from (select
[store].[state].[MI] on 0
from [myCube]
where [store].[store].[042]
)
Thinking of 'inner query only filters if the filtered dimension is returned on an axis', the theory is proved wrong if I do this:
select
[measures].[sales] on 0
from (select
[store].[state].members on 0
from [myCube]
where [store].[store].[042]
)
The sub-select still returns one state MI, but the outer query returns sales of all stores (of all states).
----EDIT 4/13----:
Re-phrasing the question in AdventureWorks cube with screenshot.
Query 1: sales of one store
Query 2: it returns sales of all stores if where clause is in the sub-select.
Query 3: the two answers I got suggested that we select the dimension in an axis - here is the result - we get all cities.
select
[measures].[sales] on 0
from (select
from [MyCube]
where [store].[store].[042]
)
The above query reduces the scope of stores just to the member [042]. Make note that sub-select is executed before the actual select. So, when it comes to the select, the engine just sees a cube which has all the members in all the dimensions; but only the member [store].[store].[042] in the store dimension. It's as if the cube has been kept intact every where else but sliced off on the Store dimension.
If you go a step ahead and add the store on to one of the axes, like
select
[measures].[sales] on 0,
[store].[store].members on 1
from (select
from [MyCube]
where [store].[store].[042]
)
you would see that although the member [All] appears in the output, it actually is just comprised of only one store.
In essence, the [All] is a special member which is calculated with respect to scope of the cube. It reflects the combined effect of all the members in the cube.
In SQL terms, it is similar to:
select sales, store as [All] from
(select sales, store from tbl where store = '042') tbl
Even though you see Sales----All, it is but a reflection of sales for store [042]
Here are some other good references concerning sub-select and slicer debate:
http://bisherryli.com/2013/02/08/mdx-25-slicer-or-sub-cube/
https://cwebbbi.wordpress.com/2014/04/07/free-video-on-subselects-in-mdx/
Chris Webb's video being located here:
https://projectbotticelli.com/knowledge/what-is-a-subselect-mdx-video-tutorial?pk_campaign=tt2014cwb
This should still leave an All member:
SELECT
[measures].[sales] ON 0
FROM
(
SELECT
FROM [MyCube]
WHERE
[store].[store].[042]
);
...but the member [All] of the Store hierarchy will only now be made up of [store].[store].[042].
You can see this by adding the Store hierarchy onto ROWS:
SELECT
[measures].[sales] ON 0,
[store].MEMBERS ON 1
FROM
(
SELECT
FROM [MyCube]
WHERE
[store].[store].[042]
);
This is the AdvWorks version similar to the reference in your question:
SELECT
{[Measures].[Order Count]} ON 0
,[Subcategory].MEMBERS ON 1
FROM
(
SELECT
{
[Subcategory].[Subcategory].&[22]
} ON 0
FROM [Adventure Works]
);
It returns the member from the sub-select and the All member adjusted to take account of the subselect:
In the references article why is the [All] less than the sum of the other two - this is not down to the subselect but is in connection with the measure that he has chosen [Measures].[Order Count] which is a distinct count. If you take away the subselect you see exactly the same behaviour of the All member being less than the sum of the other subcategory members (I've marked the point at which the total of the parts becomes higher than the All member):
SELECT
{[Measures].[Order Count]} ON 0
,Order
(
[Subcategory].MEMBERS
,[Measures].[Order Count]
,bdesc
) ON 1
FROM [Adventure Works];
Order Count: on 1 order there might be several Product Subcategories - hence this behaviour.
Edit
This query of yours:
select
[measures].[sales] on 0
from (select
[store].[state].members on 0
from TestCube //<< added this!
where [store].[store].[042]
)
This inner script is not valid? Using the same dimension on an axes and the WHERE clause is not valid:
select
[store].[state].members on 0
from TestCube
where [store].[store].[042]
Edit2
An mdx script returns a cube, which may be sliced or not sliced, but nevertheless it returns a cube. The WHERE clause is used to slice the cube that is returned. If we were using a third party tool then the dimension added to the WHERE clause would go into a combobox - with say Cliffside selected. BUT the user could effectively select Ballard from that combobox - it is just a slicer. The WHERE clause is not changing the cube that is returned by the mdx script, it is just affecting what is displayed in the cellset.
WHERE is valid within a subselect. It is part of the definition:
https://msdn.microsoft.com/en-us/library/ff487138.aspx
I've never found a use case for a subselect's WHERE clause.
Edit3
This link will explain things:
https://social.msdn.microsoft.com/Forums/sqlserver/en-US/ccb66ac3-0f9a-4261-8ccc-b6ecc51b6f07/is-where-clause-pointless-inside-a-subselect?forum=sqlanalysisservices
As Darren gosbell says in the answer to this question:
https://msdn.microsoft.com/en-us/library/ff487138.aspx it says that:
The WHERE clause does not filter the subspace.

MDX Query Join Two Dimensions

I have an MDX query as follows:
WITH
MEMBER [MatCode] AS [Product].[Material]
SELECT
([MatCode]) on 0,
([Activity].[ActivityCode].[T-50051151]) ON 1
FROM
[Cube]
This returns a value such as:
MatCode
T-50051151 Null
Which tells me it is not joining the activity code to the description when I know they match up
How can I correct my MDX query to join activity code to material?
thanks
Why not try something like the following to look for areas of the cube with data? You'll can use the WHERE clause to slice by a specific measure in your cube.
SELECT
{[Activity].[ActivityCode].[T-50051151]} ON 0,
//NON EMPTY //<<include to hide nulls
{[Product].[Material].members} on 1
FROM
[Cube]
WHERE
([Measures].[someMeasure])
Your query returns the _ default _ value / cell for the tuple :
( [Activity].[ActivityCode].[T-50051151], [Product].[Material].defaultMember )
as well as the .defaultMember for every other dimension not mentionned in your query. There is nothing wrong with it.

MDX - Count of Filtered CROSSJOIN - Performance Issues

BACKGROUND: I've been using MDX for a bit but I am by no means an expert at it - looking for some performance help. I'm working on a set of "Number of Stores Authorized / In-Stock / Selling / Etc" calculated measures (MDX) in a SQL Server Analysis Services 2012 Cube. I had these calculations performing well originally, but discovered that they weren't aggregating across my product hierarchy the way I needed them to. The two hierarchies predominantly used in this report are Business -> Item and Division -> Store.
For example, in the original MDX calcs the Stores In-Stock measure would perform correctly at the "Item" level but wouldn't roll up a proper sum to the "Business" level above it. At the business level, we want to see the total number of store/product combinations in-stock, not a distinct or MAX value as it appeared to do originally.
ORIGINAL QUERY RESULTS: Here's an example of it NOT working correctly (imagine this is an Excel Pivot Table):
[FILTER: CURRENT WEEK DAYS]
[BUSINESS] [AUTH. STORES] [STORES IN-STOCK] [% OF STORES IN STOCK]
[+] Business One 2,416 2,392 99.01%
[-] Business Two 2,377 2,108 93.39%
-Item 1 2,242 2,094 99.43%
-Item 2 2,234 1,878 84.06%
-Item 3 2,377 2,108 88.68%
-Item N ... ... ...
FIXED QUERY RESULTS: After much trial and error, I switched to using a filtered count of a CROSSJOIN() of the two hierarchies using the DESCENDANTS() function, which yielded the correct numbers (below):
[FILTER: CURRENT WEEK DAYS]
[BUSINESS] [AUTH. STORES] [STORES IN-STOCK] [% OF STORES IN STOCK]
[+] Business One 215,644 149,301 93.90%
[-] Business Two 86,898 55,532 83.02%
-Item 1 2,242 2,094 99.43%
-Item 2 2,234 1,878 99.31%
-Item 3 2,377 2,108 99.11%
-Item N ... ... ...
QUERY THAT NEEDS HELP: Here is the "new" query that yields the results above:
CREATE MEMBER CURRENTCUBE.[Measures].[Num Stores In-Stock]
AS COUNT(
FILTER(
CROSSJOIN(
DESCENDANTS(
[Product].[Item].CURRENTMEMBER,
[Product].[Item].[UPC]
),
DESCENDANTS(
[Division].[Store].CURRENTMEMBER,
[Division].[Store].[Store ID]
)
),
[Measures].[Inventory Qty] > 0
)
),
FORMAT_STRING = "#,#",
NON_EMPTY_BEHAVIOR = { [Inventory Qty] },
This query syntax is used in a bunch of other "Number of Stores Selling / Out of Stock / Etc."-type calculated measures in the cube, with only a variation to the [Inventory Qty] condition at the bottom or by chaining additional conditions.
In its current condition, this query can take 2-3 minutes to run which is way too long for the audience of this reporting. Can anyone think of a way to reduce the query load or help me rewrite this to be more efficient?
Thank you!
UPDATE 2/24/2014: We solved this issue by bypassing a lot of the MDX involved and adding flag values to our named query in the DSV.
For example, instead of doing a filter command in the MDX code for "number of stores selling" - we simply added this to the fact table named query...
CASE WHEN [Sales Qty] > 0
THEN 1
ELSE NULL
END AS [Flag_Selling]
...then we simply aggregated these measures as LastNonEmpty in the cube. They roll up much faster than the full-on MDX queries.
It should be much faster to model your conditions into the cube, avoiding the slow Filter function:
If there are just a handful of conditions, add an attribute for each of them with two values, one for condition fulfilled, say "cond: yes", and one for condition not fulfilled, say "cond: no". You can define this in a view on the physical fact table, or in the DSV, or you can model it physically. These attributes can be added to the fact table directly, defining a dimension on the same table, or more cleanly as a separate dimension table referenced from the fact table. Then define your measure as
CREATE MEMBER CURRENTCUBE.[Measures].[Num Stores In-Stock]
AS COUNT(
CROSSJOIN(
DESCENDANTS(
[Product].[Item].CURRENTMEMBER,
[Product].[Item].[UPC]
),
DESCENDANTS(
[Division].[Store].CURRENTMEMBER,
[Division].[Store].[Store ID]
),
{ [Flag dim].[cond].[cond: yes] }
)
)
Possibly, you even could define the measure as a standard count measure of the fact table.
In case there are many conditions, it might make sense to add just a single attribute with one value for each condition as a many-to-many relationship. This will be slightly slower, but still faster than the Filter call.
I believe you can avoid the cross join as well as filter completely. Try using this:
CREATE MEMBER CURRENTCUBE.[Measures].[Num Stores In-Stock]
AS
CASE WHEN [Product].[Item Name].CURRENTMEMBER IS [Product].[Item Name].[All]
THEN
SUM(EXISTS([Product].[Item Name].[Item Name].MEMBERS,[Business].[Business Name].CURRENTMEMBER),
COUNT(
EXISTS(
[Division].[Store].[Store].MEMBERS,
(
[Business].[Business Name].CURRENTMEMBER,
[Product].[Item Name].CURRENTMEMBER
),
"Measure Group Name"
)
))
ELSE
COUNT(
EXISTS(
[Division].[Store].[Store].MEMBERS,
(
[Business].[Business Name].CURRENTMEMBER,
[Product].[Item Name].CURRENTMEMBER
),
"Measure Group Name"
)
)
END
I tried it using a dimension in my cube and using Area-Subsidiary hierarchy.
The case statement handles the situation of viewing data at Business level. Basically, the SUM() across all members of Item Names used in CASE statement calculates values for individual Item Names and then sums up all the values. I believe this is what you needed.

Filtering dimensions in MDX inside a SUM

I am new to MDX expressions and I am trying to create one that sums the value of a given measure filtered by dimensions.
In my database I have several different dimensions that have the same name: "Answer". To sum them up, I have created the query below:
WITH MEMBER Measures.Total as SUM ({[Activity].[Activity].&[14], [Activity][Activity].&[22]},
[Measures].[Activity time])
SELECT NON EMPTY [Measures].[Total] on COLUMNS from [My Analytics]
This query works, however I had to use the "&[14]" and "&[22]" statments that correspond to two different "Answer" dimensions.
Since I have more than two dimensions with the same name, is there a way to rewrite the query above in a way that I would select all these dimensions without having to add their unique ID? For example, I would re-write the query as something like this:
WITH MEMBER Measures.Total as SUM ({[Activity].[Activity].&["Answer"]},
[Measures].[Activity time])
SELECT NON EMPTY [Measures].[Total] on COLUMNS from [My Analytics]
Is this possible?
Thanks!
You can use the Filter function as following:
with
set [my-answers] as
Filter( [Activity].[Activity].members,
[Activity].[Activity].currentMember.name = 'Answer'
)
member [Measures].[Total] as Sum( [my-answers] )
...

Filtering a Measure (or Removing Outliers)

Say I have a measure, foo, in a cube, and I have a reporting requirement that users want to see the following measures in a report:
total foo
total foo excluding instances where foo > 10
total foo excluding instances where foo > 30
What is the best way to handle this?
In the past, I have added Named Calculations which return NULL if foo > 10 or just foo otherwise.
I feel like there has to be a way to accomplish this in MDX (something like Filter([Measures].[foo], [Measures].[foo] > 10)), but I can't for the life of me figure anything out.
Any ideas?
The trick is that you need to apply the filter on your set, not on your measure.
For example, using the usual Microsoft 'warehouse and sales' demo cube, the following MDX will display the sales for all the stores where sales were greater than $2000.
SELECT Filter([Store].[Stores].[Store].members, [Unit Sales] > 2000) ON COLUMNS,
[Unit Sales] ON ROWS
FROM [Warehouse and Sales]
I met similar problem when use saiku (backend with Mondrain), as I haven't found any clear solution of "add filter on measure", I added it here, and that may be useful for other guy.
In Saiku3.8, you could add filter on UI: "column"->"filter"->"custom", then you may see a Filter MDX Expression.
Let's suppose we want clicks in Ad greater than 1000, then add the following line there:
[Measures].[clicks] > 1000
Save and close, then that filter will be valid for find elem with clicks greater than 1000.
The MDX likes below (suppose dt as dimension and clicks as measure, we want to find dt with clicks more than 1000)
WITH
SET [~ROWS] AS
Filter({[Dt].[dt].[dt].Members}, ([Measures].[clicks] > 1000))
SELECT
NON EMPTY {[Measures].[clicks]} ON COLUMNS,
NON EMPTY [~ROWS] ON ROWS
FROM [OfflineData]
i think you have two choices:
1- Add column to your fact(or view on data source view that is based on fact table)like:
case when unit_Price>2000 then 1
else 0
end as Unit_Price_Uper_Or_Under_10
and add a fictitious Dimension based on this columns value.
and add named query for New Dimension(say Range_Dimension in datasourceview :
select 1 as range
union all
select 0 as range
and after taht you cant used this filter like other dimension and attribute.
SELECT [Store].[Stores].[Store].members ON COLUMNS,
[Unit Sales] ON ROWS
FROM [Warehouse and Sales]
WHERE [Test_Dimension].[Range].&[1]
the problem is for every range you must add When condition and only if the range is static this solution is a good solution.
and for dynamic range it's better to formulate the range (based on disceretizing method )
2- add dimension with granularity near fact table based on fact table
for example if we have fact table with primary key Sale_id.we can add
dimension based on fact table with only one column sale_Id and in dimension Usage tab
we can relate this new dimension and measure group with relation type Fact and
after that in mdx we can use something like :
filter([dim Sale].[Sale Id].[Sale Id].members,[Measures].[Unit Price]>2000)