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What's the difference of $host and $http_host in Nginx
In Nginx, what's the difference between variables $host and $http_host .
1 Answer
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How can I avoid running ActiveRecord callbacks?
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This solution is Rails 2 only.
I just investigated this and I think I have a solution. There are two ActiveRecord private methods that you can use:
update_without_callbacks
create_without_callbacks
You're going to have to use send to call these methods. examples:
p = Person.ne...
How to check if element has any children in Javascript?
... (as opposed to text nodes, attribute nodes, etc.) on all modern browsers (and IE8 — in fact, even IE6) you can do this: (thank you Florian!)
if (element.children.length > 0) { // Or just `if (element.children.length)`
// It has at least one element as a child
}
That relies on the child...
Connection timeout for SQL server
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Yes, you could append ;Connection Timeout=30 to your connection string and specify the value you wish.
The timeout value set in the Connection Timeout property is a time expressed in seconds. If this property isn't set, the timeout value for the connection is the default value (15 seconds).
Mo...
How to update the value stored in Dictionary in C#?
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Just point to the dictionary at given key and assign a new value:
myDictionary[myKey] = myNewValue;
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Assigning variables with dynamic names in Java
...However, this only works for variables that are class members (i.e. static and instance fields). It doesn't work for local variables. See @fyr's "quick and dirty" example.
However doing this kind of thing unnecessarily in Java is a bad idea. It is inefficient, the code is more complicated, and s...
How can I tell if a DOM element is visible in the current viewport?
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Update: Time marches on and so have our browsers. This technique is no longer recommended and you should use Dan's solution if you do not need to support version of Internet Explorer before 7.
Original solution (now outdated):
This will check if ...
How to compare variables to undefined, if I don’t know whether they exist? [duplicate]
In JavaScript you can declare a variable and if it’s undefined , you can check variable == undefined ; I know that, but how can you compare a value that you don’t know yet if it’s in memory?
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How does a debugger work?
...ary the one that can be 'attached' to already running executable. I understand that compiler translates code to machine language, but then how does debugger 'know' what it is being attached to?
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Display open transactions in MySQL
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How can I display these open transactions and commit or cancel them?
There is no open transaction, MySQL will rollback the transaction upon disconnect.
You cannot commit the transaction (IFAIK).
You display threads using
SHOW FULL PROCESSLIST
See: http:/...