New RPD Modeling Features in OBIEE 11g
New
Features in OBIEE 11gR1 for Data Modeling
- ID Columns for Descriptive Columns (“Double-columns”)
- Lookup Tables
- Support for Ragged, Skip-Level and Parent-Child Hierarchies
- Hierarchical Subject Area Columns
- LTS Priority Ordering
- Repository Passwords
- Deployment of Repository Files using Fusion Middleware Control
Lookup
Tables : - LOOKUP
function introduced with OBIEE 11g allows lookups on logical and physical
tables
Useful
for several scenarios
- Pushing currency conversions to separate calculations
- Accessing columns that cannot use GROUP BY (e.g. CLOB)
- Avoiding unnecessary outer joins in LTS.
It allows
you to define a logical table as being a lookup table and can be accessed via a
logical calculation using SPARSE or DENSE lookup.
Ragged
and Skip-Level Logical Dimensions
Level based hierarchies may have
skip-levels, or ragged hierarchies. Skip levels are when members may not have
an immediate parent and Ragged hierarchies are when leaf members are not all at
the same level.
Ragged and Skipped Level Hierarchies are present in the underlying tables in
the form of NULL values
LTS
PRIORITY GROUP ORDER
A single
logical table can have multiple logical table sources defined. Usually, the
selection of LTS by the BI Server is straightforward and defined by the context
of the query. When multiple aggregate LTS are defined, however which one is
chosen id difficult to determine.
OBIEE
11gR1 LTS Priority group order makes this more explicit.
Lower
Value = Higher Priority
LTS Priority Group becomes main
decider in which LTS to use.
Let’s consider an example
A logical
fact table has two LTS mapped; one detailed level and one aggregate
By
default aggregate source is used for aggregate queries.
This
behavior will be over-ridden when LTS priority ordering is amended.
Setting
it to 1 makes it lower priority than the detail-level LTS
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