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What is Normalisation (or Normalization)?
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Normalization is basically to design a database schema such that duplicate and redundant data is avoided. If some piece of data is duplicated several places in the database, there is the risk that it is updated in one place but not the other, lead...
Why is address zero used for the null pointer?
...emory, because it means freeing the pointer again isn't dangerous; when I call malloc it returns a pointer with the value zero if it can't get me memory; I use if (p != 0) all the time to make sure passed pointers are valid, etc.
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Very slow compile times on Visual Studio 2005
...t half-way down the page):
In decreasing order of speedup:
Install Microsoft hotfix 935225.
Install Microsoft hotfix 947315.
Use a true multicore processor (ie. an Intel Core Duo 2; not a Pentium 4 HT).
Use 3 parallel builds. In Visual Studio 2005, you will find the option in Tool...
Kill a postgresql session/connection
How can I kill all my postgresql connections?
20 Answers
20
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Access POST values in Symfony2 request object
... without a class, and get back an array of the submitted
data. This is actually really easy:
public function contactAction(Request $request) {
$defaultData = array('message' => 'Type your message here');
$form = $this->createFormBuilder($defaultData)
->add('name', 'text')
->add('...
Ternary operation in CoffeeScript
...placement for what is supposed to be a concise expression. And ?: is after all a very ingrained standard among many languages, JavaScript among them. Notwithstanding all that, it seems to be set in stone at this stage.]
– mahemoff
Nov 15 '14 at 3:16
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How to get Git to clone into current directory
...it .
From git help clone:
Cloning into an existing directory is only allowed if the directory is empty.
So make sure the directory is empty (check with ls -a), otherwise the command will fail.
share
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MySQL join with where clause
...s the subset of user_category_subscriptions with a user_id of 1 to join to all of the rows in categories. This will give you all of the rows in categories, while only the categories that this particular user has subscribed to will have any information in the user_category_subscriptions columns. Of c...
compareTo() vs. equals()
...ls() because to me this seems to be the most natural method for it. After all, its name already says what it is intended to do. However, a colleague of mine recently told me had been taught to use compareTo() == 0 instead of equals() . This feels unnatural (as compareTo() is meant to provide a...
Building big, immutable objects without using constructors having long parameter lists
...of course completely wrong.
The trick is that only the build() method actually creates a Foo (hence you Foo can be immutable).
FooFactory.create(), whereXXX(..) and withXXX(..) all create "something else".
That something else may be a FooFactory, here's one way to do it....
You FooFactory would ...