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Why there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT clause?
...TAMP and ON UPDATE
CURRENT_TIMESTAMP clauses. In addition, these clauses now can be used
with DATETIME column definitions. For more information, see Automatic
Initialization and Updating for TIMESTAMP and DATETIME.
http://dev.mysql.com/doc/relnotes/mysql/5.6/en/news-5-6-5.html
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Why should I declare a virtual destructor for an abstract class in C++?
I know it is a good practice to declare virtual destructors for base classes in C++, but is it always important to declare virtual destructors even for abstract classes that function as interfaces? Please provide some reasons and examples why.
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How do I generate a random int number?
...inning point, the trigger which instigates him to select the RANDOM value.
Now if a SEED is easy to guess then those kind of random numbers are termed as PSEUDO and when a seed is difficult to guess those random numbers are termed SECURED random numbers.
For example a person chooses is color depend...
Why does “pip install” inside Python raise a SyntaxError?
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I know for me I had to do this from the command line (not python command line). This was after changing directory to the location of python.exe and then needed to put the file type on pip3. In my case I was after requests for HT...
Can you connect to Amazon ElastiСache Redis outside of Amazon?
...iCache Redis instance in a VPC from EC2 instances . But I would like to know if there is a way to connect to an ElastiCache Redis node outside of Amazon EC2 instances, such as from my local dev setup or VPS instances provided by other vendors.
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How often should you use git-gc?
...hurt to run it more frequently than needed, though.
What I'd do is run it now, then a week from now take a measurement of disk utilization, run it again, and measure disk utilization again. If it drops 5% in size, then run it once a week. If it drops more, then run it more frequently. If it drop...
Visual Studio 2013 and BitBucket
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Sorry to tag onto an old question, but know how to add multiple remotes? I want to try out TFS as a remote git server, but want to also commit to github periodically to be safe.
– Neil
Nov 6 '13 at 2:37
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PHP append one array to another (not array_push or +)
...', 'b');
$b = array('c', 'd');
$merge = array_merge($a, $b);
// $merge is now equals to array('a','b','c','d');
Doing something like:
$merge = $a + $b;
// $merge now equals array('a','b')
Will not work, because the + operator does not actually merge them. If they $a has the same keys as $b, it...
My pull request has been merged, what to do next?
...ontribute to'.
It is easier to:
delete your fix branch (actually, it is now deleted for you) on your fork (and in your local cloned repo: see "Delete a Git branch both locally and remotely")
git pull upstream master (if master was the branch in which your fix has been integrated: the merge will b...
How to write LaTeX in IPython Notebook?
...doing, found a better solution with some more searching, IPython notebooks now have a %%latex magic that makes the whole cell Latex without the $$ wrapper for each line.
Refer notebook tour for Rich Display System
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