line item dimension good / bad ?

[Former Member]

Hello Experts,

Mulling over to decide whether we can have the billing document number as a line item dimension in case 1) Accounting doc cube 2) in the Billing doc cube

Possible disadvantages:

1) if the fact table is more than 1 million records, performance improvement of using the line item dimension is not significant (is this assumption correct ???)

2) if billing document is not in the default view of the report. there is not much use it having as a line item dimension ( is this assumption correct ???)

3) if any changes are additions needs to be done to the line item dimension is not possible therefore making anything as line item dimension is not favourable. (is this the usual case ???)

Any suggestions and experiences appreciated.

Thanks,

BWer

[Former Member · Accepted solution]

Hi,

<i>1) if the fact table is more than 1 million records, performance improvement of using the line item dimension is not significant (is this assumption correct ???)</i>

No, Still it follows it role to improve the performance

<i>2) if billing document is not in the default view of the report. there is not much use it having as a line item dimension ( is this assumption correct ???)</i>

No, this is wrong conclusion

<i>3) if any changes are additions needs to be done to the line item dimension is not possible therefore making anything as line item dimension is not favourable. (is this the usual case ???)</i>

Yes. line item dimension is favourable, for the high-cardinality characteristic (high number of distinct values)

With rgds,

Anil Kumar Sharma .P

[Former Member · Accepted solution]

Keep in mind the BW history, where in early versions, Infocubes were the only reporting option, but now you cn report on an ODS. Having a high cadinality item like a document number makes your fact table larger (more rows). It would be better to have users query summarized data in the cube and jump to the ODS when they need to see document number level detail. If they always need to see document number detail, maybe you consider only doing reporting from the ODS.

If you do put the document number in the cube -

I would agree with Anil on all 3 items.

As for the 1 million row size you mention, have you seen something published some where - I'd like to see it.

Keep in mind, we're talking in generalities. Also - different databases do things differently and hav other strengths and weaknesses - that is - they ar not all exactly the same, so things might be different for Oracle vs SQL Server for instance in some cases.

[edwin_harpino]

Line Item Dimensions

Benefits

&#56256;&#56459; Saves one table join at query runtime

&#56256;&#56459; Saves determination of dimension ID’s at data load time

Disadvantages

&#56256;&#56459; F4 – Help not possible on dimension values (only on master data values)