And once you've got over these initial issues you can move on to the Mistakes People Who've Figured Out a Thing or Two About Databases Make: - storing their i

And once you've got over these initial issues you can move on to the Mistakes People Who've Figured Out a Thing or Two About Databases Make: - storing their images externally, but forgetting to apply a consistent backup strategy to their image data - Database is getting big, query returns lots of records, so just adding pagination. Forgetting that the user really doesn't actually want to page through results at all. The correct answer was probably to add proper faceted filters and full text search. - using UUID keys everywhere, then making the mistake of mixing up UUID keys from one table with UUIDs from another one. - Using nullable columns as a tool for schema change, but not deciding what it actually means for a particular column in a row to contain a NULL. - Thinking that they will get away with just storing a chunk of structured data like an array in a particular column value because from the application point of view it's really just one blob of data anyway. In general I give a structured datatype like that two days before someone is writing a query that digs into the inner structure of it.