T : +44 (0) 8446 697 995 or (888) 631 1410 (USA) E : [email protected] W: www.rittmanmead.com
Agenda
• Introduction • Business Problem • Approach • Design Considerations • Observations • Wins • Summary • Q&A • What it is not....Introductions
• Rittman Mead Consulting ‣ Oracle BI Consultancy
‣ Platinum Partner
‣ Long(est) running Oracle BI blog
‣ Annual BI Forum
‣ OBIEE Oracle Press book
• On-line retailer
‣ UK based and leading
‣ Internet based
• Jon Mead
T : +44 (0) 8446 697 995 or (888) 631 1410 (USA) E : [email protected] W: www.rittmanmead.com
Business Problem
A retail organisation needs to be able to make
pricing and purchasing (supply) decisions
based on a near real time view of what is
happening in the its marketplace (demand).
Business Problem
Competitive
Advantage
T : +44 (0) 8446 697 995 E : [email protected] W: www.rittmanmead.com
Some examples in retail
• How many units did we sell last month? • Do suppliers meet delivery targets?
• Are retail promotions attracting additional trade? • What is the lifetime value of a customer?
• How is the credit crunch affecting our sales?
• What would happen if we sold a new product line based on a customer’s likelihood to buy?
Business Problem
• Very fast changing market • Key Drivers
‣ Optimise product line
‣ Optimise pricing
‣ Optimise stock levels
• Coupled with
‣ Fraud analysis
‣ Customer tracking
‣ Order tracking
• Maximise profit
• Maximise customer satisfaction • Turn data into information quicker
T : +44 (0) 8446 697 995 or (888) 631 1410 (USA) E : [email protected] W: www.rittmanmead.com
Business Problem
Current Planned
Data Up to a monthly lag on certain data
Near real time
Queries Could take up to 24
hours
What would be needed
• Ability to process large volumes of data ‣ Volume of data
- 1000’s of transactions a minute at peak periods
‣ Complexity of the transformation
- Order lifecycle
• Ability to report on large volumes of data ‣ Year on year reporting
‣ Cross fact analysis
T : +44 (0) 8446 697 995 or (888) 631 1410 (USA) E : [email protected] W: www.rittmanmead.com
What would be needed
Fast
Data
What would be needed
Fast
Data
Processing
Fast
Data
T : +44 (0) 8446 697 995 or (888) 631 1410 (USA) E : [email protected] W: www.rittmanmead.com
Architecture
• Change Data Capture ‣ Asynchronous
• Oracle Warehouse Builder ‣ SCD Framework
• Oracle Reference Data Warehouse Architecture ‣ Staging ‣ ODS ‣ Performance layer • OBIEE ‣ Dashboards ‣ Answers
Performance ODS Staging Exa da ta CDC
T : +44 (0) 8446 697 995 or (888) 631 1410 (USA) E : [email protected] W: www.rittmanmead.com
Design considerations
• Do we change the design for Exadata? ‣ Best practices
‣ Performance
‣ Where is processing done
• Do we need a Data Warehouse? ‣ Data quality
‣ Tracking dimensional change
‣ Combining sources in OBIEE with high volumes of data can lead to performance problems WHATEVER the data source
• Preconceptions
‣ Don’t use indexes
Observations (1)
• It seems as the memory-intensive processes such as SQL analytics perform roughly the same
‣ However Exadata does have a lot of RAM so PGA should be large
• IO intensive operations are lightning fast.
T : +44 (0) 8446 697 995 or (888) 631 1410 (USA) E : [email protected] W: www.rittmanmead.com
Observations (2)
• Parallelism and hence performance works best with partition-wise operations ‣ HASH partition on business keys for dimensions
‣ Would have been good to HASH the fact on the same key for partition-wise joins on same RAC node
- Reduce interconnect traffic
- SCD may prevent this anyway
‣ RANGE partitioning may reduce performance benefits of HASH partitioning, however it make archival easier
• Indexes
‣ Still useful when a specific rows required, e.g. tree-walking with CONNECT BY PRIOR
Observations (3)
• Advanced compression ‣ Big gain was disk space
• Sequences
‣ Must increase size of Sequence pool
‣ Common to all RAC instances
• Patching
‣ There is still some complexity in the patching process
• Not a magic wand
‣ It is still possible to produce badly designed star schemas
‣ It is still possible to produce badly designed OBIEE repositories
T : +44 (0) 8446 697 995 or (888) 631 1410 (USA) E : [email protected] W: www.rittmanmead.com
Wins - the numbers...
• ETL
‣ 10 facts; 15 dimensions; 300 tables; 157 OWB mappings
- Daily load: 1 hour 30 minutes
- Daily load : approximately 130 million rows pushed through staging area and into the ODS and the Data Warehouse
‣ One of the facts is refreshed with approximately 100 million rows and only takes 10 minutes
• Reporting
‣ Reports could be run over multiple fact over multiple years
‣ Report that took 24 hours to run now completes in 15 minutes
Summary
• Benefits
‣ Organisation now has near real time supply and demand data
‣ Ad-hoc reporting capability
‣ Reduced turnaround of generating reports from 2 to 3 days of spreadsheet crunching to instant available dashboard
‣ One source of truth (no spreadsheets)
• Made possible by
‣ Extreme performance in the ETL layer
T : +44 (0) 8446 697 995 or (888) 631 1410 (USA) E : [email protected] W: www.rittmanmead.com