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MySQL, Check if a column exists in a table with SQL
... query that will check if a specific table in MySQL has a specific column, and if not — create it. Otherwise do nothing. This is really an easy procedure in any enterprise-class database, yet MySQL seems to be an exception.
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Best way to represent a fraction in Java?
...too long ago, for Project Euler problems. It keeps a BigInteger numerator and denominator, so it'll never overflow. But it'll be a tad slow for a lot of operations that you know will never overflow.. anyway, use it if you want it. I've been dying to show this off somehow. :)
Edit: Latest and gre...
Difference between std::system_clock and std::steady_clock?
What is the difference between std::system_clock and std::steady_clock ? (An example case that illustrate different results/behaviours would be great).
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Regex to match only letters
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Use a character set: [a-zA-Z] matches one letter from A–Z in lowercase and uppercase. [a-zA-Z]+ matches one or more letters and ^[a-zA-Z]+$ matches only strings that consist of one or more letters only (^ and $ mark the begin and end of a string respectively).
If you want to match other letters...
Overflow-x:hidden doesn't prevent content from overflowing in mobile browsers
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Creating a site wrapper div inside the <body> and applying the overflow-x:hidden to the wrapper instead of the <body> or <html> fixed the issue.
It appears that browsers that parse the <meta name="viewport"> tag simply ignore overflow attributes on t...
Are custom elements valid HTML5?
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The Custom Elements specification is available in Chrome and Opera, and becoming available in other browsers. It provides a means to register custom elements in a formal manner.
Custom elements are new types of DOM elements that can be defined by
authors. Unlike decorators, which ...
Significance of a .inl file in C++
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.inl files are never mandatory and have no special significance to the compiler. It's just a way of structuring your code that provides a hint to the humans that might read it.
I use .inl files in two cases:
For definitions of inline functions...
How can I create an Asynchronous function in Javascript?
...iscussing this with a friend yesterday so this answer is perfect! I understand and can identify the async functions and use them in JS properly. But simply why can't we implement custom ones is not clear to me. It's like a black box that we know how make it work (using, say, setInterval) but that we...
Cookies on localhost with explicit domain
...sic thing about cookies. On localhost, when I set a cookie on server side and specify the domain explicitly as localhost (or .localhost). the cookie does not seem to be accepted by some browsers.
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Deleting queues in RabbitMQ
... about the data in management database; i.e. users, vhosts, messages etc., and neither about other queues, then you can reset via commandline by running the following commands in order:
WARNING: In addition to the queues, this will also remove any users and vhosts, you have configured on your Ra...