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Querying a dim's column in star join HANA view why result in entire view execution (PlanViz))

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We are at HANA SP11 and BO 4.1 SP3 patch 2 with webi connecting to relational universe (Hana biz layer) to HANA star join calc. views. View under questions has star join with fact surrounded by left join with dimension calc views.

 

I am just trying to get LOVs for a dimension column without reference to any other column like
select DISTINCT DimColumn1 from view


and this column is not calculated column (anyway why it should matter unless it refers fact or any other view)


Also note, this behavior happens irrespective of whether I query directly on HANA studio or through BO IDT


Query takes very long time for result and our report prompt screen becomes slow. When I see plan viz, it shows query is going to entire fact table etc which confuses me why its doing so ?? I have just queried one column from dimension in star join.

 

As a temporary mitigation, we are bringing dim calc. view in universe and creating LOVs. When we started using star join , we thought this will have benefit of star schema. However, we are  seeing none.

SAP support says  "oh we see your plan viz it's doing what it's supposed to do". and our discussion still going on.

 

So two questions :

1) Why do you think its behaving that way ? Is there anything we could be doing wrong - given its star join, left outer join fact and dim, querying only one non-calculated column from dim

2) From your experience, how do you guys achieve same i.e. creating LOVs from similar setup of BO-HANA through relational universe so that only dim column view gets invoked

 

Further Info:-

-- There is left outer join b/w Fact and Dim

-- Non of join column are calculated column

-- There is no design time filter on Dim view


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