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MySQL Error 1093 - Can't specify target table for update in FROM clause
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Update: This answer covers the general error classification. For a more specific answer about how to best handle the OP's exact query, please see other answers to this question
In MySQL, you can't modify the same table which you use i...
MIN and MAX in C
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Where are MIN and MAX defined in C, if at all?
They aren't.
What is the best way to implement these, as generically and type safe as possible (compiler extensions/builtins for mainstream compilers preferred).
As functions. I wouldn't use macros like #define MIN(X, Y) (((X) < (Y)) ? (X...
python design patterns [closed]
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Intermediate and Advanced Software Carpentry in Python
Code Like a Pythonista: Idiomatic Python
Python Idioms and Efficiency
Google Developers Day US - Python Design Patterns
Another resource is by example at the Python Recipes. A good number do not follow best practices but you can find some ...
Python logging not outputting anything
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The default logging level is warning.
Since you haven't changed the level, the root logger's level is still warning.
That means that it will ignore any logging with a level that is lower than warning, including debug loggings.
This is explained in th...
Transitions on the CSS display property
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You can concatenate two transitions or more, and visibility is what comes handy this time.
div {
border: 1px solid #eee;
}
div > ul {
visibility: hidden;
opacity: 0;
transition: visibility 0s, opacity 0.5s linear;
}
div:hover > ul {
visibility: ...
Logic to test that 3 of 4 are True
...instance, in C++:
if ((int)a + (int)b + (int)c + (int)d == 3)
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This is well defined in C++: the standard (§4.7/4) indicates that converting bool to int gives the expected values 0 or 1.
In Java and C#, you can use the following construct:
if ((a?1:0) + (b?1:0) + (c?1:0) + (d?1:0) == 3)
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What's the “average” requests per second for a production web application?
...e of reference in terms of what's considered "fast"; I'd always wondered this but have never found a straight answer...
8 A...
Press alt + numeric in bash and you get (arg [numeric]) what is that?
Press alt + numeric in bash and you get (arg [numeric]) what is that?
7 Answers
7
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Difference between object and class in Scala
...cala tutorials on the Internet and have noticed in some examples an object is declared at the start of the example.
13 Answ...
How to detect Adblock on my website?
I would like to be able to detect if the user is using adblocking software when they visit my website. If they are using it, I want to display a message asking them to turn it off in order to support the project, like this website does.
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