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Difference between 3NF and BCNF in simple terms (must be able to explain to an 8-year old)
...in BCNF because there is no column (either key or non-key) that is functionally dependent on anything besides that key.
Because each pizza must have exactly one of each topping type, we know that (Pizza, Topping Type) is a candidate key. We also know intuitively that a given topping cannot belong ...
No mapping found for field in order to sort on in ElasticSearch
... I still have the problem but I want the documents to be in the results in all cases even if they don't have the attribute.
– c4k
Oct 27 '13 at 15:47
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Can you nest html forms?
... I agree with the answer, but to ask another, why not? Why does HTML not allow for nesting forms? To me, it appears to be a limitation that we would be better off without. There are many examples where using nested forms would be easier to program (i.e. using an upload photo form with a profile ed...
How can I prevent SQL injection in PHP?
...is way it is impossible for an attacker to inject malicious SQL.
You basically have two options to achieve this:
Using PDO (for any supported database driver):
$stmt = $pdo->prepare('SELECT * FROM employees WHERE name = :name');
$stmt->execute([ 'name' => $name ]);
foreach ($stmt as $...
JavaScript open in a new window, not tab
I have a select box that calls window.open(url) when an item is selected. Firefox will open the page in a new tab by default. However, I would like the page to open in a new window, not a new tab.
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Pragma in define macro
...ay of doing that. Then again, there are no portable ways to use #pragma at all. Because of this, many C/C++ compilers define their own methods for doing pragma-like things, and they often can be embedded in macros, but you need a different macro definition on every compiler. If you are willing to go...
Which icon sizes should my Windows application's icon include?
... 24, 32, 40, 48, 64, 96, 128 and 256. Then I checked which image is shown. All these were done with normal 96dpi. If using a larger DPI, the larger sizes may be used (only checked this a bit in Windows 7). The results:
Windows XP:
Explorer views:
Details / List: 16
Icons: 32
Tiles / Thumbnails: 48...
sql “LIKE” equivalent in django query
...s. I have made the lookup into a Django-like-lookup application. After installing it the __like lookup with the % and _ wildcards will be enabled.
All the necessary code in the application is:
from django.db.models import Lookup
from django.db.models.fields import Field
@Field.register_lookup
cl...
Binding an enum to a WinForms combo box, and then setting it
...dView.CurrentRow.Cells["comboColumnCell"].Value. I can see value but internally it throws null pointer exception
– ssal
Jun 5 '14 at 17:18
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Why isn't ProjectName-Prefix.pch created automatically in Xcode 6?
Why isn't ProjectName-Prefix.pch created automatically in Xcode 6 ?
8 Answers
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