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UICollectionView reloadData not functioning properly in iOS 7
...l UIKit related messages. I seem to run into this when popping to the view from another view controller. I refresh the data on viewWillAppear. I could see the data and collection view reload call, but the UI was not updated. Forced the main thread (UI thread), and it magically starts working. Th...
What is a serialVersionUID and why should I use it?
...d it preserves the abiity of the serialVersionUID mechanism to protect you from incompatible changes.
– Tom Anderson
Apr 24 '11 at 10:43
25
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Does a foreign key automatically create an index?
... tables.
Foreign key columns are often used in join criteria when the data from related tables is combined in queries by matching the column(s) in the FOREIGN KEY constraint of one table with the primary or unique key column(s) in the other table. An index allows Microsoft® SQL Server™ 2000 to fi...
How can I represent an 'Enum' in Python?
... numbers) will install a completely different and incompatible version.
from enum import Enum # for enum34, or the stdlib version
# from aenum import Enum # for the aenum version
Animal = Enum('Animal', 'ant bee cat dog')
Animal.ant # returns <Animal.ant: 1>
Animal['ant'] # returns ...
NOT using repository pattern, use the ORM as is (EF)
... exception
Do you code for the 1% chance your database is going to change from one technology to another? If you're thinking about your business's future state and say yes that's a possibility then a) they must have a lot of money to afford to do a migration to another DB technology or b) you're ch...
Is inline assembly language slower than native C++ code?
...
Yes, most times.
First of all you start from wrong assumption that a low-level language (assembly in this case) will always produce faster code than high-level language (C++ and C in this case). It's not true. Is C code always faster than Java code? No because ther...
How can I open multiple files using “with open” in Python?
... of files all at the same time, you can use contextlib.ExitStack, starting from Python version 3.3:
with ExitStack() as stack:
files = [stack.enter_context(open(fname)) for fname in filenames]
# Do something with "files"
Most of the time you have a variable set of files, you likely want t...
Calculate difference in keys contained in two Python dictionaries
...ge for python:
https://github.com/seperman/deepdiff
Installation
Install from PyPi:
pip install deepdiff
Example usage
Importing
>>> from deepdiff import DeepDiff
>>> from pprint import pprint
>>> from __future__ import print_function # In case running on Python 2
...
Best Practices: Salting & peppering passwords?
...you do hash_function($salt . hash_function($pepper . $password)).
We know from past experience that "just feeding" one hash result into another hash function can decrease the overall security. The reason is that both hash functions can become a target of attack.
That's why algorithms like PBKDF2 ...
Why does Javascript getYear() return 108?
...issues now that getYear() has been deprecated in favour of getFullYear() - from quirksmode:
To make the matter even more complex, date.getYear() is deprecated nowadays and you should use date.getFullYear(), which, in turn, is not supported by the older browsers. If it works, however, it should alwa...