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Community Wiki answer for the various links originally left as comments on this popular question How does a surname of Null cause problems in many databases? (Programmers SE) Falsehoods Programmers Believe About Names by Patrick McKenzie Licensed to Bill by David Mikkelson (snopes.com) An example of coding that will cause this issue in the application ...


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There's plenty of poorly written software, and even frameworks, that would behave oddly with somebody named Null. But let's not forget the human element: perhaps humans seeing the name on screens and printouts and thinking it's a mistake and deleting the person is another likely cause?


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One thing I don't think I've seen mentioned: We aren't just talking about SQL. The name might start/end in the database... but to get there normally involves MULTIPLE channels. Database, Sql, php, html, javascript... Java, C#, VB, Perl, Phython, Ruby, bash, batch, etc, etc, etc... Each of these steps in the pipeline might involve converting data from one ...


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The article itself includes a link to a Stack Overflow question that demonstrates the problem; it was in a Flex application where the code: currentChild.appendChild("Fred"); would append an element containing the word Fred to an XML document but the code: currentChild.appendChild("null"); would append an empty element, not an element containing the ...


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There's a good chance that a good chunk of your confusion stems from the journalist's. The article talks about problems using entire application systems, not just databases. Completely reasonable since this is a piece of writing aimed at mass consumption, but technical details are glossed over or misunderstood by the author. Likely a number of these issues ...


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Relational databases have to accommodate missing or irrelevent values. For example, the list of customers may include a mobile phone number or a gender. What if a corporation wants to become a customer - what gender should it have? A special indicator is used to show a value is missing. This special flag is NULL. So sloppy programming may cause the missing ...


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I have seen database interfaces (e.g. framework libraries) that return 'null' as a string for null columns. I believe there was a flag that would turn this on or off for debugging. This flag allows developers to easily determine if the empty field was a result of a null value or an empty value. This is a bad setting, especially in production, and would ...



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