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Rails :include vs. :joins
...de functionality was changed with Rails 2.1. Rails used to do the join in all cases, but for performance reasons it was changed to use multiple queries in some circumstances. This blog post by Fabio Akita has some good information on the change (see the section entitled "Optimized Eager Loading")....
For loop for HTMLCollection elements
I'm trying to set get id of all elements in an HTMLCollectionOf . I wrote the following code:
12 Answers
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IE8 support for CSS Media Query
...ous rules.
For example:
<link rel="stylesheet" type="text/css" media="all" href="style.css"/>
<!--[if lt IE 9]>
<link rel="stylesheet" type="text/css" media="all" href="style-ie.css"/>
<![endif]-->
This won't allow for a responsive design in IE8, but could be a simpler an...
MySQL/Amazon RDS error: “you do not have SUPER privileges…”
... The -f option will not make the errors go away, it will just allow the non-offending SQL statements in the file to be processed. From what I've read, RDS is choking on stored procedures in the dump file. Try creating a dump file without store procedures and see if that loads OK: mysqld...
Xcode 5.1 - No architectures to compile for (ONLY_ACTIVE_ARCH=YES, active arch=x86_64, VALID_ARCHS=i
...from the workspace in the left pane of Xcode and close Xcode.
Run "pod install" from the command line to recreate the "Pods" project.
Re-open Xcode and make sure "Build Active Architecture Only" is set to "No" in the build settings of both the "Pods" project and your own project.
Clean and build.
...
Qt: can't find -lGL error
I just reinstalled QtCreator, created new project ( Qt Application ) an got this after compilation:
8 Answers
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Why are primes important in cryptography?
...
Most basic and general explanation: cryptography is all about number theory, and all integer numbers (except 0 and 1) are made up of primes, so you deal with primes a lot in number theory.
More specifically, some important cryptographic algorithms such as RSA critically depen...
How to detect online/offline event cross-browser?
...nows that
such an attempt would fail), and must
return true otherwise.
Finally, the spec notes:
This attribute is inherently
unreliable. A computer can be
connected to a network without having
Internet access.
share
...
How do HttpOnly cookies work with AJAX requests?
...st to the server.
In the case of Stack Overflow, the cookies are automatically provided as part of the XmlHttpRequest request. I don't know the implementation details of the Stack Overflow authentication provider, but that cookie data is probably automatically used to verify your identity at a low...
Fitting empirical distribution to theoretical ones with Scipy (Python)?
...error is determined. The distribution with the least error is returned.
All Distributions
Best Fit Distribution
Example Code
%matplotlib inline
import warnings
import numpy as np
import pandas as pd
import scipy.stats as st
import statsmodels as sm
import matplotlib
import matplotlib.pypl...