what is aggregate navigation?

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what is aggregate navigation?..

Whenever we use Aggregate Aware we need to set up
incompatilibities to work it properly (so BusinessObjects
knows what SQL to generate)

For example, There are 2 aggregate tables fact table by
week and by day.If you set up a measure as aggregate aware
from both tables - total quantity for example, the select
might be something like: -

@Aggregate_Aware(sum(week_agg.qty),sum(day_agg.qty))

The week table listed first as this would be the
preference. But as BusinessObjects needs a reason to not go
to the week_agg table, this is done using
incompatibilities. For example the Week Number dimension
object would be compatible with the week_agg table as it
will link to it and the data is held at an appropriate
level to report against it. However the Date dimension
object would be set as incompatible with the week_agg
table, such that when it is selected alongside the Quantity
object, BusinessObjects knows to jump to the next option in
its select definition.

Is This Answer Correct ?

27 Yes

3 No

what is aggregate navigation?..

Answer / nareshkumar

Aggregate Navigation is used to specify the incompatible
objects.

Is This Answer Correct ?

20 Yes

7 No

what is aggregate navigation?..

Answer / sam

To receive the performance benefit offered by an aggregate
schema, a query must be written to use the aggregate.
Rewriting the sample query was a simple matter of
substituting the name of the aggregate fact table for that
of the base fact table. This may be easy for technical
personnel, but can prove confusing for an end user. The
complexity grows as additional aggregate tables are added.
Technical and business users alike may err in assessing
which table will provide the best performance. And, if more
aggregate tables are added or old ones removed, existing
queries must be rewritten.
The key to avoiding these pitfalls lies in implementation
of an aggregate navigator.
A component of the data warehouse infrastructure, the
aggregate navigator assumes the task of rewriting user
queries to utilize aggregate tables.
Users and developers need only be concerned with the base
schema. At runtime, the aggregate navigator redirects the
query to the most efficient aggregate schema.