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What's the use/meaning of the @ character in variable names in C#?
...nt in PHP software for variables. And a lot of Open Source web systems are now coded in C# (where in the past it would have been PHP)
– Wasted_Coder
Mar 5 '16 at 19:36
...
pandas three-way joining multiple dataframes on columns
...
This is decent advice and has now been incorporated into pandas merging 101 (see the section on merging multiple dataframes). It's worth noting that if your join keys are unique, using pd.concat will result in simpler syntax: pd.concat([df.set_index('name...
Adding a guideline to the editor in Visual Studio
... for a light grey: RGB(221, 221, 221).
Here are the registry keys that I know of:
Visual Studio 2010: HKCU\Software\Microsoft\VisualStudio\10.0\Text Editor
Visual Studio 2008: HKCU\Software\Microsoft\VisualStudio\9.0\Text Editor
Visual Studio 2005: HKCU\Software\Microsoft\VisualStudio\8.0\Text E...
HTTP GET request in JavaScript?
...
I know some people want to write pure Javascript. I get that. I have no problem with people doing that in their projects. My "In jQuery:" should be intpreted as "I know you asked how to do it in Javascript, but let me show yo...
Cannot resolve the collation conflict between “SQL_Latin1_General_CP1_CI_AS” and “Latin1_General_CI_
...
marc i'm getting this now: Cannot alter or drop column because it is enabled for Full-Text Search.
– jhowe
Oct 22 '09 at 14:58
...
implements Closeable or implements AutoCloseable
...se() throws Exception {
System.out.println("Closing!");
}
}
Now you can say:
try (MyResource res = new MyResource()) {
// use resource here
}
and JVM will call close() automatically for you.
Closeable is an older interface. For some reason To preserve backward compatibility, l...
What are database normal forms and can you give examples? [closed]
...es |
IT103 | 2009-2 | 120 | 242 | Mrs Smith |
Now hopefully it should be obvious that TeacherName is dependent on TeacherID - so this is not in 3NF. To fix this, we do much the same as we did in 2NF - take the TeacherName field out of this table, and put it in its own, w...
Linux: copy and create destination dir if it does not exist
... might have a shell that doesn't support this construct. However, I don't know of any modern shells that don't support $_; certainly Bash, Dash, and zsh all do.
A final note: the command I've given at the start of this answer assumes that your directory names don't have spaces in. If you're deali...
MYSQL OR vs IN performance
...
I needed to know this for sure, so I benchmarked both methods. I consistenly found IN to be much faster than using OR.
Do not believe people who give their "opinion", science is all about testing and evidence.
I ran a loop of 1000x the ...
Make an HTTP request with android
...
Note: The Apache HTTP Client bundled with Android is now deprecated in favor of HttpURLConnection. Please see the Android Developers Blog for more details.
Add <uses-permission android:name="android.permission.INTERNET" /> to your manifest.
You would then retrieve a web...