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Does MySQL ignore null values on unique constraints?
I have an email column that I want to be unique. But I also want it to accept null values. Can my database have 2 null emails that way?
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How do you reference a capture group with regex find and replace in Visual Studio 2012, 2013, 2015,
I realize there are a ton of questions about this, but none that I found specifically referenced which VS version they referred to. With that important information lacking, I still was unable to successfully use the answers I found. The most common was
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Create table in SQLite only if it doesn't exist already
I want to create a table in a SQLite database only if doesn't exist already. Is there any way to do this? I don't want to drop the table if it exists, only create it if it doesn't.
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instantiate a class from a variable in PHP?
I know this question sounds rather vague so I will make it more clear with an example:
5 Answers
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How to access route, post, get etc. parameters in Zend Framework 2
How can I get various parameters related to the page request in zf2? Like post/get parameters, the route being accessed, headers sent and files uploaded.
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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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What's the difference between Html.Label, Html.LabelFor and Html.LabelForModel
What's the difference between @Html.Label() , @Html.LabelFor() and @Html.LabelForModel() methods?
4 Answers
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How to write inline if statement for print?
I need to print some stuff only when a boolean variable is set to True . So, after looking at this , I tried with a simple example:
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Releasing memory in Python
I have a few related questions regarding memory usage in the following example.
4 Answers
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