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Another Repeated column in mapping for entity error
Despite all of the others post, I can't find a solution for this error with GlassFish, on MacOSX, NetBeans 7.2.
8 Answers
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Using str_replace so that it only acts on the first match?
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There's no version of it, but the solution isn't hacky at all.
$pos = strpos($haystack, $needle);
if ($pos !== false) {
$newstring = substr_replace($haystack, $replace, $pos, strlen($needle));
}
Pretty easy, and saves the performance penalty of regular expressions.
Bonus: If...
Check if Internet Connection Exists with Javascript? [duplicate]
...browsers, doing so with older web browsers may not work as expected, or at all.
Alternatively, an XHR request to your own server isn't that bad of a method for testing your connectivity. Considering one of the other answers state that there are too many points of failure for an XHR, if your XHR is ...
config.assets.compile=true in Rails production, why not?
The default Rails app installed by rails new has config.assets.compile = false in production.
7 Answers
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brew install mysql on macOS
I'm trying to setup up MySQL on mac os 10.6 using Homebrew by brew install mysql 5.1.52 .
16 Answers
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ANTLR: Is there a simple example?
...r, and evaluator using ANTLR4.
You first create a grammar. Below is a small grammar that you can use to evaluate expressions that are built using the 4 basic math operators: +, -, * and /. You can also group expressions using parenthesis.
Note that this grammar is just a very basic one: it does ...
Hide grid row in WPF
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UpVoted - Converters permit all this to be declarative in Xaml. I generally hate using code-behind to fiddle with visual stuff.
– Allen
May 22 '14 at 13:43
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JavaScript checking for null vs. undefined and difference between == and ===
...is the difference between the null and undefined?
They're both values usually used to indicate the absence of something. undefined is the more generic one, used as the default value of variables until they're assigned some other value, as the value of function arguments that weren't provided when ...
Linear Regression and group by in R
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fits <- lmList(response ~ year | state, data=d)
fits
#------------
Call: lmList(formula = response ~ year | state, data = d)
Coefficients:
(Intercept) year
CA -1.34420990 0.17139963
NY 0.00196176 -0.01852429
Degrees of freedom: 20 total; 16 residual
Residual standard error: 0.820...
System.currentTimeMillis() vs. new Date() vs. Calendar.getInstance().getTime()
...ost efficient since it does not even create an object, but new Date() is really just a thin wrapper about a long, so it is not far behind. Calendar, on the other hand, is relatively slow and very complex, since it has to deal with the considerably complexity and all the oddities that are inherent to...