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How do MySQL indexes work?
...e name came from):
Let's say you have a book about databases and you want to find some information about, say, storage. Without an index (assuming no other aid, such as a table of contents) you'd have to go through the pages one by one, until you found the topic (that's a full table scan).
On the ...
How to configure a HTTP proxy for svn
I want to check code from the repository http://code.sixapart.com/svn/perlbal/ . I can only access the the repository url by setting a proxy. I guess if I want to get the code from the same URL by svn I need to configure a proxy, too. So does anyone of you could tell me how to configure a HTTP pro...
What is the most efficient way to deep clone an object in JavaScript?
What is the most efficient way to clone a JavaScript object? I've seen obj = eval(uneval(o)); being used, but that's non-standard and only supported by Firefox . I've done things like obj = JSON.parse(JSON.stringify(o)); but question the efficiency. I've also seen recursive copying funct...
cocoapods - 'pod install' takes forever
I was trying to update the existing pods with pod install command, but it takes forever to run.
19 Answers
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How to combine multiple conditions to subset a data-frame using “OR”?
I have a data.frame in R. I want to try two different conditions on two different columns, but I want these conditions to be inclusive. Therefore, I would like to use "OR" to combine the conditions. I have used the following syntax before with lot of success when I wanted to use the "AND" conditio...
How to disable an input type=text?
I want to disable writing in an input field of type text using JavaScript, if possible.
The input field is populated from a database; that is why I don't want the user to modify its value.
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Why is it Valid to Concatenate Null Strings but not to Call “null.ToString()”?
... value of the original null string.
More information on the + binary operator:
The binary + operator performs string concatenation when one or both operands are of type string.
If an operand of string concatenation is null, an empty string is substituted. Otherwise, any non-string argument is conv...
How to use __doPostBack()
I'm trying to create an asyncrhonous postback in ASP.NET using __doPostBack() , but I have no idea how to do it. I want to use vanilla JavaScript.
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Test PHP headers with PHPUnit
I'm trying to use PHPunit to test a class that outputs some custom headers.
7 Answers
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Git stash: “Cannot apply to a dirty working tree, please stage your changes”
I am trying to apply changes I stashed earlier with git stash pop and get the message:
11 Answers
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