Last week Claudia Imhoff wrote a post titled: ‘The ODS is alive and well, thank you very much‘. It is good that every once in a while people challenge our thinking to allow us to regroup and clarify the purpose and value of our thinking.
I agree that the Operational Data Store (ODS) is not dead, it is even more important than ever. Here is an excerpt from her post on what the heck this thing is:
1. Subject-oriented – The ODS is built similarly to the data
warehouse in that its data content is focused about different data
subjects. Examples of data subjects are customer, product, and order
data.2. Integrated – the data from each subject area is fully integrated
– again much like the data in the data warehouse. It is cleaned up as
much as is technologically and humanly possible during the ETL process
before it is populated into the store.3. Current – the data in the ODS is as current as we can
technologically make it – a significant difference from a traditional
data warehouse. Current as in as close to “real time” as we can get.
The data probably won’t be synchronous with the operational system
source because of the latencies inherent with integration but it will
be close.4. Volatile – major differentiator from a data warehouse. The new or
changed data flowing into the ODS updates the appropriate records or
fields exactly like you would update a record in an OLTP operational
system. For example, when a new customer address is brought in, the old
customer address is overwritten. An audit trail is created to trace the
change but the old data is gone. If you want the history of the
customer’s moves, you will have to either go to the audit trail or the
data warehouse where history is preserved in snapshots.
The in teresting thing about the use of data today is that the demands are ever challenging our previous ideas and the technology os constantly evolving. Whether it is the evolution of appliances (Netezza, DATAllegro) or the change of Data Integration (Sunopsis, Ascential) there is an evolving and more important need for our reference architecture to keep us on track.
In a comment on this post, an additional value other than as the source for the datawarehouse or operational reporting, but cleansing or fixing the data. As we have all experienced, our lovely source systems are often untouchable from a practical or political point. So we always have the issue of the best place to solve data quality is at the source, but we are often not allowed to do so. So the ODS allows us to get darn close to this by using this is our platform and now calling this the system of record for our data. Sound like master data management – yup. So now we have a place for record master data. Maybe not the history, but that is not the purpose of this.
So now introduce modern equipment like Teradata and we can have the ODS live in the enterprise data warehouse. Now we have also reduced our effort needed for data integration and movement of data.
Thanks Claudia for bringing up this topic.
