Switching management software is daunting mostly because of the data. Customers, items, prices, outstanding debts, years of invoices and job history: it is all in the old system, and nobody wants to retype it or lose it. Data migration is a part of the project that tends to be underestimated and that, if planned properly, can be done without nasty surprises. This article explains how.
Decide which data you need to bring over
The first temptation is to bring everything. That is not always a good idea: the more you bring, the more you have to clean, transform and check. Split your data into three groups:
| Group | Examples | What to do |
|---|---|---|
| Master data | Customers, suppliers, items, price lists, construction sites, farms, employees | Bring them over, clean and reviewed |
| Live data | Open orders, invoices awaiting payment, current stock, jobs in progress | Bring them over with an exact cut-off date |
| History | Invoices, delivery notes and movements from previous years | Decide: bring everything, bring the last few years, or leave it available for consultation in the old system |
For the history, think about what you use it for. If it is to compare sales with previous years, the totals may be enough. If it is to look up a specific invoice when a customer asks for it, it can stay in the old system in read-only mode, or be exported to a readable format.
What you cannot throw away
Not migrating the history does not mean you can delete it. The Código de Comercio (Spanish Commercial Code), article 30, requires businesses to keep their books, correspondence, documentation and supporting records for six years, and the Ley General Tributaria (Spanish General Tax Act), article 66, sets the limitation period for tax debts at four years in general, so tax documentation must remain available at least while that period is open. Some sector-specific regulations have their own deadlines. Before switching off the old system, make sure that whatever you must keep is still accessible and readable, and check with your accountant which deadlines apply to you.
The reverse also applies: the Reglamento General de Protección de Datos (Reglamento (UE) 2016/679, General Data Protection Regulation), article 5, requires that personal data not be kept longer than necessary. Migration is a good opportunity not to carry over to the new system records of people you have had no relationship with for years and whom you are not obliged to keep.
Clean up before migrating
An old system accumulates years of small messes. If they are moved across as they are, the new system will start out with the same problems. At the very least, check:
- Duplicates. The same customer registered three times under slightly different names.
- Inactive records. Items that have not sold for years, suppliers that no longer exist.
- Misused fields. Phone numbers in the notes field, addresses split across several fields, codes made up on the fly.
- Incomplete data. Customers without a tax ID (NIF), items without a family, employees without a category.
- Formats. Dates, decimals, capitals and accents that the old system stored in its own way.
The clean-up has to be done or validated by someone in your company. The supplier can spot duplicates, but only you know whether “Hnos. Pérez” and “Hermanos Pérez S.L.” are the same customer.
The steps of an orderly migration
- Extract. Get the data out of the old system. If it has an export function, great; if not, you may need to access its database. Check beforehand who holds the passwords and whether your contract with the old supplier allows it.
- Map fields. Draw up a table showing which field in the new system each field in the old one goes to, and what is done with anything that has no equivalent.
- Transform. Standardise codes, formats and units. This is where you decide, for example, whether items keep their code or are recoded.
- Load in a test environment. Do a first load in a test environment, never directly in the live one.
- Check. Review using data you know well (we explain below).
- Repeat. Correct and reload as many times as needed. It is normal for it to take several rounds.
- Final load with a cut-off date. Choose the moment, freeze the old system and carry out the final load.
How to check that everything has arrived correctly
- Count records. The same number of customers, items and invoices in both systems, minus whatever you decided not to bring over.
- Reconcile totals. Outstanding receivables, stock value, billing for a specific month. They must match.
- Review familiar records. Pick ten customers and ten items you know well and compare them field by field.
- Test the daily work. Have the people who use the system create an order, an invoice or a complete work report with migrated data.
- Review the odd cases. Customers with special price lists, items with several units, corrected documents.
Changeover day
Choose a quiet time, such as a month-end close or the low season, and avoid the start of a campaign. Give the team plenty of notice that the old system cannot be worked in on that day. Keep the old system available in read-only mode for a while and make a full copy of its data before touching anything. For the first few days, have someone on hand who can answer questions and fix migration errors that only show up once people start working.
Common mistakes
- Leaving the migration until the end of the project, when there is no time left to repeat it.
- Migrating without cleaning up and then blaming the new system for the errors.
- Not checking the totals and discovering the mismatch when closing the quarter.
- Deleting or decommissioning the old system before securing access to the history.
- Not involving the people who know the data.
How we do it at Infonet
At Infonet Consultores, migrating the data you already have is part of the roll-out, along with installation, configuration and training, whether we are implementing one of our applications or developing a bespoke program. Our own team does it and then continues to provide direct support. You can see how we work in bespoke software development and the applications we implement on the home page.
