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Simple explanation of MapReduce?
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Going all the way down to the basics for Map and Reduce.
Map is a function which "transforms" items in some kind of list to another kind of item and put them back in the same kind of list.
suppose I have a list of numbers: [1,2...
SQL query return data from multiple tables
...I-89 syntax (and if you are used to 89, may seem much less intuitive - but all I can say is to try it) as it is much easier to understand when the queries start getting more complex. Why use it? Is there a performance gain? The short answer is no, but it is easier to read once you get used to it. It...
How can I clear an HTML file input with JavaScript?
...d the file input element to this new form and reset it. This way works for all browsers.
I wrote a javascript function. demo: http://jsbin.com/muhipoye/1/
function clearInputFile(f){
if(f.value){
try{
f.value = ''; //for IE11, latest Chrome/Firefox/Opera...
}catch(...
How can I use Google's Roboto font on a website?
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You don't really need to do any of this.
Go to Google's Web Fonts page
search for Roboto in the search box at the top right
Select the variants of the font you want to use
click 'Select This Font' at the top and choose the weights an...
Intellij IDEA, format all code in a project
I really like IDEA's code formatting, but how do I get it to reformat all the code in a particular project without going through each file? I've found the option to tidy / optimise imports on code before committing it to subversion which is great, but it only seems to apply to files that have otherw...
What is a 'Closure'?
... scope
When you declare a local variable, that variable has a scope. Generally, local variables exist only within the block or function in which you declare them.
function() {
var a = 1;
console.log(a); // works
}
console.log(a); // fails
If I try to access a local variable, most languag...
How do I check that multiple keys are in a dict in a single pass?
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Well, you could do this:
>>> if all (k in foo for k in ("foo","bar")):
... print "They're there!"
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They're there!
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Does svn have a `revert-all` command?
If I want to throw away all of my changes, and return to the code that is on the repository, I do the following:
4 Answers
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ASP.NET MVC ambiguous action methods
I have two action methods that are conflicting. Basically, I want to be able to get to the same view using two different routes, either by an item's ID or by the item's name and its parent's (items can have the same name across different parents). A search term can be used to filter the list.
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Creating a copy of a database in PostgreSQL [closed]
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Postgres allows the use of any existing database on the server as a template when creating a new database. I'm not sure whether pgAdmin gives you the option on the create database dialog but you should be able to execute the following...