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MySQL, better to insert NULL or empty string?
I have a form on a website which has a lot of different fields. Some of the fields are optional while some are mandatory. In my DB I have a table which holds all these values, is it better practice to insert a NULL value or an empty string into the DB columns where the user didn't put any data?
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Join/Where with LINQ and Lambda
I'm having trouble with a query written in LINQ and Lambda. So far, I'm getting a lot of errors here's my code:
9 Answers
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When to use Amazon Cloudfront or S3
Are there use cases that lend themselves better to Amazon cloudfront over s3 or the other way around? I'm trying to understand the difference between the 2 through examples.
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MySQL ON vs USING?
In a MySQL JOIN , what is the difference between ON and USING() ? As far as I can tell, USING() is just more convenient syntax, whereas ON allows a little more flexibility when the column names are not identical. However, that difference is so minor, you'd think they'd just do away with USI...
How do I write JSON data to a file?
I have JSON data stored in the variable data .
14 Answers
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How can I push a local Git branch to a remote with a different name easily?
I've been wondering if there's an easy way to push and pull a local branch with a remote branch with a different name without always specifying both names.
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Meaning of -
I am new to XML and I am trying to understand the basics. I read the line below in "Learning XML", but it is still not clear, for me. Can someone point me to a book or website which explains these basics clearly?
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Painless way to install a new version of R?
Andrew Gelman recently lamented the lack of an easy upgrade process for R (probably more relevant on Windows than Linux). Does anyone have a good trick for doing the upgrade, from installing the software to copying all the settings/packages over?
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Computational complexity of Fibonacci Sequence
I understand Big-O notation, but I don't know how to calculate it for many functions. In particular, I've been trying to figure out the computational complexity of the naive version of the Fibonacci sequence:
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Can regular expressions be used to match nested patterns? [duplicate]
Is it possible to write a regular expression that matches a nested pattern that occurs an unknown number of times? For example, can a regular expression match an opening and closing brace when there are an unknown number of open/close braces nested within the outer braces?
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