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Why can't a text column have a default value in MySQL?
If you try to create a TEXT column on a table, and give it a default value in MySQL, you get an error (on Windows at least). I cannot see any reason why a text column should not have a default value. No explanation is given by the MySQL documentation. It seems illogical to me (and somewhat frustrati...
Why does Python use 'magic methods'?
I've been playing around with Python recently, and one thing I'm finding a bit odd is the extensive use of 'magic methods', e.g. to make its length available, an object implements a method, def __len__(self) , and then it is called when you write len(obj) .
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Algorithm to generate all possible permutations of a list?
... left to right, all the permutations of the remaining items are generated (and each one is added with the current elements). This can be done recursively (or iteratively if you like pain) until the last item is reached at which point there is only one possible order.
So with the list [1,2,3,4] all ...
src/lxml/etree_defs.h:9:31: fatal error: libxml/xmlversion.h: No such file or directory
... Notice for Ubuntu 13.04 users: if you have libxml2 already installed and upgraded to version 2.9.0+dfsg1-4ubuntu4.3 you need to downgrade it to 2.9.0+dfsg1-4ubuntu4.1 by typing the command sudo apt-get install libxml2=2.9.0+dfsg1-4ubuntu4.1 otherwise the libxml2-dev wont be installed due versi...
std::enable_if to conditionally compile a member function
I am trying to get a simple example to work to understand how to use std::enable_if . After I read this answer , I thought it shouldn't be too hard to come up with a simple example. I want to use std::enable_if to choose between two member-functions and allow only one of them to be used.
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Flexbox: center horizontally and vertically
How to center div horizontally, and vertically within the container using flexbox. In below example, I want each number below each other (in rows), which are centered horizontally.
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How does a “stack overflow” occur and how do you prevent it?
How does a stack overflow occur and what are the best ways to make sure it doesn't happen, or ways to prevent one, particularly on web servers, but other examples would be interesting as well?
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Python Pandas merge only certain columns
...e to only merge some columns? I have a DataFrame df1 with columns x, y, z, and df2 with columns x, a ,b, c, d, e, f, etc.
5...
MVC DateTime binding with incorrect date format
...ur has a thorough explanation of why MVC works with dates the way it does, and how you can override this if necessary:
http://weblogs.asp.net/melvynharbour/archive/2008/11/21/mvc-modelbinder-and-localization.aspx
When looking for the value to parse, the framework looks in a specific order namel...
Is Meyers' implementation of the Singleton pattern thread safe?
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In C++11, it is thread safe. According to the standard, §6.7 [stmt.dcl] p4:
If control enters
the declaration concurrently while the variable is being initialized, the concurrent execution shall wait for completion of the initialization.
GCC and VS support for the...