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Why are joins bad when considering scalability?
...ndex for any where clause on the tables. If you don't join, mysql will typically use only one index(which might not be the most efficient one), no matter how your where clause is formed.
– leeeroy
Apr 12 '10 at 17:29
...
How to set timeout on python's socket recv method?
...elect() to wait until data is available or until the timeout occurs. Only call recv() when data is actually available. To be safe, we also set the socket to non-blocking mode to guarantee that recv() will never block indefinitely. select() can also be used to wait on more than one socket at a tim...
How do I add a class to a given element?
... of your new class to the className property of the element. First, put an id on the element so you can easily get a reference.
<div id="div1" class="someclass">
<img ... id="image1" name="image1" />
</div>
Then
var d = document.getElementById("div1");
d.className += " oth...
Computational complexity of Fibonacci Sequence
...ill have depth n and intuitively figure out that this function is asymptotically O(2n). You can then prove your conjecture by induction.
Base: n = 1 is obvious
Assume T(n-1) = O(2n-1), therefore
T(n) = T(n-1) + T(n-2) + O(1) which is equal to
T(n) = O(2n-1) + O(2n-2) + O(1) = O(2n)
However, as...
Difference between a “coroutine” and a “thread”?
...eratively multitasked by pausing and resuming functions at set points, typically (but not necessarily) within a single thread.
Long answer: In contrast to threads, which are pre-emptively scheduled by the operating system, coroutine switches are cooperative, meaning the programmer (and possibly the...
How to “fadeOut” & “remove” a div in jQuery?
I'm trying to give fadeout effect to a div & delete that div(id = "notification"), when an image is clicked.
7 Answers
...
navigator.geolocation.getCurrentPosition sometimes works sometimes doesn't
...tPosition is infinite(!). That means that your error handler will never be called if getCurrentPosition hangs somewhere on the back end.
To ensure that you get a timeout, add the optional third parameter to your call to getCurrentPosition, for example, if you want the user to wait no more than 10 s...
A proper wrapper for console.log with correct line number?
...nsole.log.bind(window.console)
else var debug = function(){}
Then simply call as follows:
debug('This is happening.')
You can even take over the console.log with a switch like this:
if (!isDebug) console.log = function(){}
If you want to do something useful with that.. You can add all the ...
Difference between array_push() and $array[] =
...
When you call a function in PHP (such as array_push()), there are overheads to the call, as PHP has to look up the function reference, find its position in memory and execute whatever code it defines.
Using $arr[] = 'some value'; doe...
socket.shutdown vs socket.close
...
Here's one explanation:
Once a socket is no longer required,
the calling program can discard the
socket by applying a close subroutine
to the socket descriptor. If a
reliable delivery socket has data
associated with it when a close takes
place, the system continues to attempt
d...