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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, ...
How can I use “puts” to the console without a line break in ruby on rails?
...oothly, you need to flush the stdout buffer after each print...
def print_and_flush(str)
print str
$stdout.flush
end
100.times do
print_and_flush "."
sleep 1
end
Edit: I was just looking into the reasoning behind flush to answer @rubyprince's comment, and realised this could be cleaned u...
cannot download, $GOPATH not set
...ults to $HOME/go, but you may still find this useful if you want to understand the GOPATH layout, customize it, etc.]
The official Go site discusses GOPATH and how to lay out a workspace directory.
export GOPATH="$HOME/your-workspace-dir/" -- run it in your shell, then add it to ~/.bashrc or equiv...
How can I convert my Java program to an .exe file? [closed]
...
javapackager
The Java Packager tool compiles, packages, and prepares Java and JavaFX applications for distribution. The javapackager command is the command-line version.
– Oracle's documentation
The javapackager utility ships with the JDK. It can generate .exe files with the -n...
Oracle TNS names not showing when adding new connection to SQL Developer
...RACLE\ORACLE_HOME
To see which one SQL Developer is using, issue the command show tns in the worksheet
If your tnsnames.ora file is not getting recognized, use the following procedure:
Define an environmental variable called TNS_ADMIN to point to the folder that contains your tnsnames.ora file....
Assign output to variable in Bash
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Is there a way to suppress the output and progress bar of curl? Adding -silent leaves $IP empty...
– Dror
Jul 14 '14 at 8:30
4
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TortoiseSVN icons not showing up under Windows 7
I can't seem to get the icons to display under Windows 7 and I really miss this from Windows XP.
31 Answers
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How to change MySQL data directory?
...
Stop MySQL using the following command:
sudo /etc/init.d/mysql stop
Copy the existing data directory (default located in /var/lib/mysql) using the following command:
sudo cp -R -p /var/lib/mysql /newpath
edit the MySQL configuration file with the following...
How to solve Permission denied (publickey) error when using Git?
I'm on Mac Snow Leopard and I just installed git .
45 Answers
45
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How to check if a file is a valid image file?
...r most image formats but not all. as per my original problem with svg, xcf and psd files, well those are undetected in imghdr as well
– Sujoy
May 26 '09 at 12:54
2
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