The importance of error checking
 
 
- Errors happen!
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- Failure happens when you don't expect errors!
- database crash / network disconnection
- lack of disk space for insert or select (sort space for order by)
- server math error on select (divide by zero after fetching 10,000 rows)
- and maybe, just maybe, errors in your own code [Gasp!]
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- Beat failure by expecting errors!
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- Detect errors early to limit effects
- Defensive Programming, e.g., check assumptions
- Through Programming, e.g., check for errors after fetch loops
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- (and undefined values are your friends: always enable warnings)