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Storing time-series data, relational or non?
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Definitely Relational. Unlimited flexibility and expansion.
Two corrections, both in concept and application, followed by an elevation.
Correction
It is not "filtering out the un-needed data"; it is selecting only the needed data. Yes, of course, if you have an Ind...
How to do ToString for a possibly null object?
...efore, while it maybe appears elegant, the cast is almost always necessary and is not that succinct in practice.
As suggested elsewhere, I recommend maybe using an extension method to make this cleaner:
public static string ToStringNullSafe(this object value)
{
return (value ?? string.Empty).ToS...
Use grep --exclude/--include syntax to not grep through certain files
...Note that the star is escaped with a backslash to prevent it from being expanded by the shell (quoting it, such as --include="*.{cpp,h}", would work just as well). Otherwise, if you had any files in the current working directory that matched the pattern, the command line would expand to something l...
How do I determine if a port is open on a Windows server? [closed]
...e default option 'telnet' is not recognized as an internal or external command, operable program or batch file. To solve this, just enable it: Click *Start** → Control Panel → Programs → Turn Windows Features on or off. In the list, scroll down and select Telnet Client and click OK.
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How to replace case-insensitive literal substrings in Java
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Not as elegant perhaps as other approaches but it's pretty solid and easy to follow, esp. for people newer to Java. One thing that gets me about the String class is this: It's been around for a very long time and while it supports a global replace with regexp and a global replace with Str...
Inline SVG in CSS
...rk nicely is Safari (5.1.4). In Opera 11.62 the gradient is black, in IE 9 and Firefox 12 it's white. In Chrome 19, it works UNLESS you specify the width/height of the SVG in % units. I'd say it's more of an oddity than a real feature. It's a cool find though.
– toniedzwiedz
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How do I encode and decode a base64 string?
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Null checks for input strings in both functions and the solution is perfect :)
– Sverrir Sigmundarson
Mar 29 '14 at 23:05
24
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What do the plus and minus signs mean in Objective-C next to a method?
In Objective-C, I would like to know what the + and - signs next to a method definition mean.
4 Answers
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How to use UIVisualEffectView to Blur Image?
...tView.frame = imageView.bounds;
[imageView addSubview:visualEffectView];
and Swift:
var visualEffectView = UIVisualEffectView(effect: UIBlurEffect(style: .Light))
visualEffectView.frame = imageView.bounds
imageView.addSubview(visualEffectView)
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区块链技术到底是什么鬼，为何被疯炒？ - 资讯 - 清泛网 - 专注C/C++及内核技术
...中管理。
举个例子：如A要转账一笔钱给B，需经过银行O进行验证、对账，再修改A、B的账户，将钱划给B。
(图5：传统货币交易模式)
而基于区块链技术的比特币交易模式则剔除了银行作为中心数据库的角色，每个比特币用户...