1. Developing with error reporting off
2. Suppressing errors
3. No logging anywhere in the code
4. Not implementing caching
5. Disregarding best practices and design patterns
6. Not using automated tests
7. Not reviewing / auditing code
8. Coding for the ideal scenario
9. Not using OOP principles correctly
10. “On-the-fly” coding
11. Not differentiating between read / write queries
12. Only coding for one database connection
13. Not testing queries for exploits
14. Not adding indexes to tables
15. Not using transactions
16. Not securing sensitive data
17. Not differentiating between development environments
18. No backup
19. No monitoring

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