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MYSQL OR vs IN performance
... not believe people who give their "opinion", science is all about testing and evidence.
I ran a loop of 1000x the equivalent queries (for consistency, I used sql_no_cache):
IN: 2.34969592094s
OR: 5.83781504631s
Update:
(I don't have the source code for the original test, as it was 6 years ago, ...
Is gcc's __attribute__((packed)) / #pragma pack unsafe?
...6 systems won't reveal the problem. (On the x86, misaligned accesses are handled in hardware; if you dereference an int* pointer that points to an odd address, it will be a little slower than if it were properly aligned, but you'll get the correct result.)
On some other systems, such as SPARC, att...
input() error - NameError: name '…' is not defined
... to input(). That is, the new input() function reads a line from sys.stdin and returns it with the trailing newline stripped. It raises EOFError if the input is terminated prematurely. To get the old behavior of input(), use eval(input())
In Python 2.7, there are two functions which can be used ...
What is INSTALL_PARSE_FAILED_NO_CERTIFICATES error?
...ge my default/main/startup (whatever you call it) activity by editing the androidmanifest.xml file. All i did was change the android:name property. however, this completely broke the entire app. when I try to install it fails and reads.
...
How to remove unused C/C++ symbols with GCC and ld?
I need to optimize the size of my executable severely ( ARM development) and
I noticed that in my current build scheme ( gcc + ld ) unused symbols are not getting stripped.
...
Importing from a relative path in Python
I have a folder for my client code, a folder for my server code, and a folder for code that is shared between them
5 Answer...
How to kill a process running on particular port in Linux?
...omcat /bin directory. But found that the server was not closed properly. And thus I was unable to restart My tomcat is running on port 8080 .
...
Broken references in Virtualenvs
...long with some other applications (I changed to iTerm instead of Terminal, and Sublime as my default text editor) but ever since, all my virtual environments have stopped working, although their folders inside .virtualenvs are still there and they give the following error whenever I try to run anyth...
Determine if Python is running inside virtualenv
...nside a virtual environment, sys.prefix points to the virtual environment, and sys.base_prefix is the prefix of the system Python the virtualenv was created from.
The above always works for Python 3 stdlib venv and for recent virtualenv (since version 20). Older versions of virtualenv used sys.real_...
Which would be better for concurrent tasks on node.js? Fibers? Web-workers? or Threads?
I stumbled over node.js sometime ago and like it a lot. But soon I found out that it lacked badly the ability to perform CPU-intensive tasks. So, I started googling and got these answers to solve the problem: Fibers, Webworkers and Threads (thread-a-gogo). Now which one to use is a confusion and one...