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MySQL, better to insert NULL or empty string?
...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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XMLHttpRequest cannot load file. Cross origin requests are only supported for HTTP
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If you are doing something like writing HTML and Javascript in a code editor on your personal computer, and testing the output in your browser, you will probably get error messages about Cross Origin Requests. Your browser will render HTML and run Javascript, jQuery, a...
How dangerous is it to compare floating point values?
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First of all, floating point values are not "random" in their behavior. Exact comparison can and does make sense in plenty of real-world usages. But if you're going to use floating point you need to be aware of how it works. Erring on the side of assuming floating point ...
Why do x86-64 instructions on 32-bit registers zero the upper part of the full 64-bit register?
...ould almost never be used. (Making int 64-bit would waste cache footprint and memory bandwidth; x86-64 most efficiently supports 32 and 64-bit operand sizes)
The behaviour for 8 and 16-bit operand sizes is the strange one. The dependency madness is one of the reasons that 16-bit instructions are a...
Is SQL or even TSQL Turing Complete?
...e programming languages, so that's kinda cheating).
In this set of slides Andrew Gierth proves that with CTE and Windowing SQL is Turing Complete, by constructing a cyclic tag system, which has been proved to be Turing Complete. The CTE feature is the important part however -- it allows you to crea...
Bootstrap Dropdown menu is not working
...n my machine. Anyone have any ideas? I have been staring at it for an hour and can't seem to figure out what the problem is.
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How can I create a two dimensional array in JavaScript?
I have been reading online and some places say it isn't possible, some say it is and then give an example and others refute the example, etc.
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SQLite UPSERT / UPDATE OR INSERT
...r in a single statement. Plus you get all the other features, improvements and bug fixes that usually come with a more recent release.
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[ :Unexpected operator in shell programming [duplicate]
...et of sh syntax - the /bin/sh executable on your system may provide only standard sh functionality, in which []-style tests are not included.
– Tim
Aug 5 '10 at 1:17
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Can PHP cURL retrieve response headers AND body in a single request?
Is there any way to get both headers and body for a cURL request using PHP? I found that this option:
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