Data Migration Done Right: Move From Spreadsheets to a Real System Safely
Why spreadsheet migrations fail (and how to avoid it)
Most migrations fail for one of these reasons:
Data is messy (duplicates, missing IDs, inconsistent formats)
No clear “source of truth” (different versions of the same sheet)
Import is done once, with no testing or reconciliation
Go-live happens without a rollback plan
A “safe migration” is not a single import—it’s a controlled process: audit → map → clean → test → cutover → verify → support.
1) Start with a migration plan (before touching the data)
Define these 6 items first:
What you are migrating (customers, products, invoices, inventory, HR…)
Where the data lives (Excel files, Google Sheets, email attachments)
Owners (who approves each dataset)
Success criteria (e.g., “0 missing customers,” “totals match,” “orders open correctly”)
Timeline & freeze window (when edits must stop)
Risks + mitigation (backup, rollback, pilot run)
2) Do a data audit (find the real problems early)
Before you map anything, check:
Duplicate customers/vendors (same phone/email with different names)
Missing required fields (IDs, tax numbers, addresses, currency)
Invalid formats (dates, phone numbers, amounts with commas)
Broken relationships (orders without customers, items without SKUs)
“Hidden logic” in spreadsheets (manual formulas that change totals)
Deliverable you want from this step: a list of issues + rules to fix them.
3) Build a data dictionary (your migration “contract”)
A data dictionary is a simple table that says:
Field name in the new system (e.g.,
customer_id)Meaning (what it represents)
Format (text/number/date)
Required? (yes/no)
Source (which sheet/column is the truth)
Validation rules (e.g., phone must be 9–15 digits)
This becomes your reference for mapping and validation.
4) Map spreadsheet columns to system fields (data mapping)
Mapping answers: “Where does each value go in the new system?”
Example:
Client Name→customers.full_namePhone→customers.mobileInvoice Total→invoices.total_amountStatus→invoices.status(with allowed values only)
Pro tip: mapping must include:
Allowed values (e.g.,
Paid / Unpaid / Partial)Default values when missing
Transformation rules (e.g., currency, date standardization)
5) Clean the data (data cleansing) — safest time to save money
Cleaning typically includes:
Standardize formats (dates, phones, currencies)
Remove duplicates (merge rules: latest record wins, or primary key wins)
Fix required fields
Normalize categories (e.g., “Cairo”, “CAIRO”, “القاهرة” → one value)
Validate relationships (customer ↔ invoices ↔ items)
Best practice: clean in a separate “staging” sheet/file, not in your original working file.
6) Test migration using a pilot import (do not start with 100%)
Run a pilot with 5–10% of the data:
Import to a staging environment
Fix errors
Repeat until error rate is near zero
Validate results with business owners (finance/ops/sales)
What to validate:
Counts (number of customers, invoices, products)
Totals (balances, invoice totals, inventory quantities)
Spot-check samples (random 20–50 records)
7) Plan the cutover (go-live) + rollback (your safety net)
A safe cutover has these steps:
Cutover checklist
Announce a freeze window (no edits in spreadsheets)
Take a final export with timestamp
Create backups/snapshots
Run the final migration
Reconcile totals
Enable users/roles, integrations, email notifications, reports
Go-live + monitor
Rollback plan (must exist)
If a critical issue appears:
Restore snapshot/backup
Revert to the old process temporarily
Fix and re-run migration
8) After go-live: verify and optimize (hypercare week)
First 7–14 days after launch:
Daily reconciliation checks
Track user issues and fix workflows
Update training and the knowledge base
Improve validation rules to prevent “new bad data”
9) Post-migration KPIs (prove success)
Track monthly:
Data accuracy (mismatch rate vs old totals)
Ticket reduction (“where is my data?” type)
Processing time (order/invoice cycle time)
Adoption (active users + feature usage)
Error rate (validation/import failures)
Audit trail coverage
Report reliability
Time/cost saved vs spreadsheet workflow