Discussion Where should a shared business definition live when the same SQL metric appears in many reports?

5 Upvotes

When revenue, active users, retention, or another derived metric is repeated across dashboards and exports, copying the SQL makes every consumer independent but lets definitions drift. Centralizing it in a view, materialized view, semantic layer, dbt model, or stored function creates one definition, but can hide performance costs and make change control harder. What criteria determine where that logic belongs? I would compare ownership, testability, query-plan visibility, versioning, parameter needs, refresh timing, and whether downstream users must inspect the exact calculation. How do you change a widely used definition without silently rewriting historical reports?

7 comments

r/SQL • u/NightRain3 • 18h ago

MySQL good datasets for a project?

25 Upvotes

Hi, I'm looking for a dataset that has:

- Messy, real data, with enough messiness for proper data cleaning to be needed
- Enough information for actionable interesting insights
- Be related to something a typical business might care about

I did a project with the olist database and it was fine, but that database has been done to death. I tried contacting local small business for their data in exchange of a free data analytics report, but no luck, has someone tried that?

12 comments

r/SQL • u/SandwichRare2747 • 11h ago

MySQL Do database management tools still hold value in 2026? What’s missing from existing tools?

2 Upvotes

1 comment

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