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<TITLE>The importance of error checking</TITLE>
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<P>Slide 42 of 102</P>
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<!-- <UL>
<H2>The importance of error checking</H2>
</UL></P>
<P><UL>
<LI><H2>Errors happen!
</H2>
<UL>
<LI>Failure happens when you don't expect errors!
<UL>
<LI>database crash / network disconnection
<LI>lack of disk space for insert or select (sort space for order by)
<LI>server math error on select (divide by zero after fetching 10,000 rows)
<LI>and maybe, just maybe, errors in your own code [Gasp!]
<LI>
</UL><LI>Beat failure by expecting errors!
<LI>
<LI>Detect errors early to limit effects
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<LI>Defensive Programming, e.g., check assumptions
<LI>Through Programming, e.g., check for errors after fetch loops
<LI>
</UL><LI>(and undefined values are your friends: always enable warnings)
</UL></UL><UL>
<H2>.</H2>
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