Move as much of the functionality as possible into SAP and make SAP manage all the data for CUP. Create a set of APIs between CUP's existing systems and build a business logic layer that would do all the transformations from how SAP handles data to how the legacy systems do things. Undertake a radical overhaul of all of CUP's internal systems so that they all use SAP's data model - SAP's view of the world.
"We chose option three. We have quite a good development capability in house and we took the line that we wanted to enhance and rewire a good chunk of our key internal systems to use the SAP data model. That in itself was a 12-month project - to redesign each application schema, to change the applications to use the new schema, to change how the data flows worked from system to system," said Rimell.
"That all went live a few months ahead of the SAP go live, to allow it to bed in. But as a result of having taken that early hit, we now have a single product data model for all our product data across all of our systems. Everything is now a straightforward data flow from one system to another."
Rimell said that putting all of the data into SAP to manage wasn't an option for CUP, as it wanted to retain its systems' publishing customisations that have been built up over the years.
"Had we done option one, the challenge there is that SAP is still not an editorial, publishing system. We have years of built-up knowledge of how to do this and we have coded up systems with that knowledge - to have thrown away those lessons learnt and systems expertise, was not a route we wanted to go down," he said.
Although Rimell said that he was pleased that up until this point he and his team had delivered the project on budget, on spec and on time, he did warn others undertaking such a large data migration that you need to factor in time for business users to assess the quality of the data.
"What does good data look like? What does bad data look like? You need someone in the business who knows. So the load that puts on the business is quite high," he said.
"For these people that are being called upon to test business processes, it puts quite a bit of burden on them. So you must remember to factor in the time it takes business users - because we did that, we hit all of our data migration deadlines."
Rimell will be speaking on behalf of Cambridge University Press at the SAP UK & Ireland User Group Conference in Birmingham this month. For more details of the event, click here.
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