Self-Taught Truck Driver Solves Flask Bakery App Data Integrity Issues with Soft Deletes

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A self-taught Python developer in Japan, who works professionally as a truck driver, documented a series of technical challenges encountered while building a bakery sales management app using Flask, PostgreSQL, and the Gemini API. A critical bug caused product deletions to break existing sales history, as recreating products generated new database IDs that severed links to past transaction records. The developer resolved this by implementing soft deletes, allowing products to be marked as discontinued rather than physically removed, preserving referential integrity. Additional fixes included lazy-loading Gemini API calls to prevent automatic quota consumption on dashboard load, and improving error messages when the free API limit was reached. The project, documented on GitHub, represents roughly 135 hours of self-directed programming study at the time of these changes.

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