PORTFOLIO PROOF
Customer Orders Data Processing & Quality Control
Independent Data Project
Training Simulation
Excel / Spreadsheet
Data Quality
Project Overview
What I Demonstrated
- Normalized customer names, email text, status labels, and core fields.
- Connected related records using Product ID lookups to retrieve product names and prices.
- Calculated order totals and reviewed the results for consistency.
- Used duplicate checks and Data Validation as part of a quality-control workflow.
- Recorded non-obvious corrections in a Change Log instead of silently changing source information.
- Flagged a zero-quantity record for review rather than inventing a value.
Before → After
| Original issue | Action | Result |
|---|---|---|
| Inconsistent names / casing | Normalization | Consistent customer names |
| Inconsistent status labels | Standardization | Usable status field |
| Product IDs without readable details | VLOOKUP | Product name + price connected to orders |
| Duplicate / incomplete inputs | COUNTIF + validation checks | Issues identified for review |
| Ambiguous / zero-quantity record | Flagged for confirmation | No fabricated correction |
Workflow
| Step | What was done | Why it matters |
|---|---|---|
| 1. Prepare | Preserved original data and created a working area. | Keeps source data auditable. |
| 2. Clean | Normalized names, emails, statuses, and fields. | Improves consistency. |
| 3. Connect | Used Product ID lookup to retrieve product and price. | Links related tables efficiently. |
| 4. Calculate | Computed totals from quantity and price. | Creates usable order values. |
| 5. Validate | Checked duplicates, completeness, and data rules. | Reduces silent errors. |
| 6. Document | Recorded important changes in a Change Log. | Makes corrections explainable. |
| 7. Deliver | Produced a structured final worksheet. | Turns raw data into a usable deliverable. |
Evidence Areas
Spreadsheet organizationData cleaning
Data normalizationLookup-based joins
CalculationsDuplicate checks
Data ValidationQuality control