Practice core MySQL functions (strings, dates, math, NULL/conditionals, aggregation) on a compact dataset from the jewelry retail industry. The SQL file in this repo creates the schema, seeds data, and includes tasks.
- Reporting-ready formatting (clean strings, case transforms, concatenation)
- Operations & logistics (weekday names, ETAs, pending vs delivered)
- Finance accuracy (rounding, per-unit price, handling fee)
- Data quality checks (NULL handling, variance between expected vs recorded totals)
These are everyday skills for BI/analytics: producing executive-friendly outputs, estimating delivery timelines, and validating order totals.
- Built queries that compose readable labels:
item – quantity – ORDER STATUS - Extracted weekday names for delivery scheduling
- Computed handling fees and per-unit prices with correct rounding
- Filtered out NULL delivery dates and flagged PENDING vs DELIVERED
- Summarized orders by month and compared expected vs recorded totals
- Produced a compact practice set you can reuse to drill MySQL functions fast
Minimal preview of the two tables joined; see the
.sqlfile for full definitions and data.
| OrderID | ItemName | Quantity | OrderDate | DeliveryDate | OrderStatus | Cost |
|---|---|---|---|---|---|---|
| 1 | Engagement ring | 50 | 2022-04-05 | 2022-05-25 | Delivered | 122000 |
| 2 | Silver brooch | 75 | 2022-03-08 | (NULL) | In progress | 28000 |
| 3 | Earrings | 80 | 2022-05-19 | 2022-06-08 | Delivered | 25000 |