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Finding duplicate values in a SQL table
...ly group on both of the columns.
Note: the older ANSI standard is to have all non-aggregated columns in the GROUP BY but this has changed with the idea of "functional dependency":
In relational database theory, a functional dependency is a constraint between two sets of attributes in a relation...
Obtain Bundle Identifier programmatically
...n approach to get the value. ARC example is following:
NSString *value = (__bridge_transfer NSString *)CFDictionaryGetValue(CFBundleGetInfoDictionary(CFBundleGetMainBundle()),
(const void *)(@"CFBundleIdentifier"));
...
jQuery table sort
...
If you want to avoid all the bells and whistles then may I suggest this simple sortElements plugin. Usage:
var table = $('table');
$('.sortable th')
.wrapInner('<span title="sort this column"/>')
.each(function(){
var th ...
MVC Razor dynamic model, 'object' does not contain definition for 'PropertyName'
...:
According to David Ebbo, you can't pass an anonymous type into a dynamically-typed view because the anonymous types are compiled as internal. Since the CSHTML view is compiled into a separate assembly, it can't access the anonymous type's properties.
EDIT #2:
David Ebbo has edited his post with...
How to check if hex color is “too black”?
...
You have to extract the three RGB components individually, and then use a standard formula to convert the resulting RGB values into their perceived brightness.
Assuming a six character colour:
var c = c.substring(1); // strip #
var rgb = parseInt(c, 16); // convert rrg...
Changing Vim indentation behavior by file type
...h a width of 2 characters for indenting (the noexpandtab option is set globally elsewhere in my configuration).
This is described here: http://vimdoc.sourceforge.net/htmldoc/usr_05.html#05.4, scroll down to the section on filetype plugins.
...
Add list to set?
...rticle. Pythons hashing algorithms are explained on effbot.org and pythons __hash__ function in the python reference.
Some facts:
Set elements as well as dictionary keys have to be hashable
Some unhashable datatypes:
list: use tuple instead
set: use frozenset instead
dict: has no official count...
How to randomize (or permute) a dataframe rowwise and columnwise?
...] 1 0 0 1 0
[4,] 0 0 1 0 1
To explain the call:
out <- permatswap(mat, times = 99, burnin = 20000, thin = 500, mtype = "prab")
times is the number of randomised matrices you want, here 99
burnin is the number of swaps made before we start taking random samples....
Setting UIButton image results in blue button in iOS 7
...
In iOS7 there is new button type called UIButtonTypeSystem NS_ENUM_AVAILABLE_IOS(7_0), // standard system button
Check your .xib file and change button type to Custom
To do this programmatically, add this line to the viewDidLoad:
[UIButton buttonWithType...
PHP Fatal error: Call to undefined function json_decode()
Apache is logging PHP Fatal error: Call to undefined function json_decode() . After some googling, it seems this problem is a result of not having the latest version of php. Oddly, running php --version ouputs
...