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What's the difference between NOT EXISTS vs. NOT IN vs. LEFT JOIN WHERE IS NULL?
...LEFT JOIN / IS NULL: Oracle
NOT IN vs. NOT EXISTS vs. LEFT JOIN / IS NULL: MySQL
In a nutshell:
NOT IN is a little bit different: it never matches if there is but a single NULL in the list.
In MySQL, NOT EXISTS is a little bit less efficient
In SQL Server, LEFT JOIN / IS NULL is less efficient
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How do you switch pages in Xamarin.Forms?
...displayed and replace its Content.
The suggested options of replacing the root page works as well, but you'll have to handle that differently for each platform.
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Ruby equivalent of virtualenv?
...s)
bundler install --binstubs --path vendor
Running this command in the root of a project will install the gems listed from your Gemfile, put the libs in ./vendor, and any executables in ./bin and all requires (if you use bundle console or the Bundler requires) will reference these exes and libs....
Sending POST data in Android
... "6 - response !empty...");
//
JSONObject jRoot = new JSONObject(response);
JSONObject d = jRoot.getJSONObject("d");
int ResultType = d.getInt("ResultType");
Log.e("ResultType", ResultType + "");
if (Re...
NERDTree reload new files
...imply hit r to refresh the current directory's listing or R to refresh the root directory's listing .
Do you see "Press ? for help" at the top of the NERDTree window? It means that you can press ? for help. If you do, you will see an exhaustive listing of NERDTree shortcuts. That's neat.
More gene...
Android: What is android.R.id.content used for?
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As Philipp Reichart commented:
android.R.id.content gives you the root element of a view, without having to know its actual name/type/ID. Check out http://stackoverflow.com/questions/4486034/android-how-to-get-root-view-from-current-activity
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How do I tell Git to ignore everything except a subdirectory?
...
This ignores root files & root directories, then un-ignores the root bin directory:
/*
/*/
!/bin/
This way you get all of the bin directory, including subdirectories and their files.
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https connection using CURL from command line
...ections.
curl -k https://whatever.com/script.php
Edit: I discovered the root of the problem. I was using an SSL certificate (from StartSSL, but I don't think that matters much) and hadn't set up the intermediate certificate properly. If you're having the same problem as user1270392 above, it's pr...
Sibling package imports
...ern on a regular basis with
# Ugly hack to allow absolute import from the root folder
# whatever its name is. Please forgive the heresy.
if __name__ == "__main__" and __package__ is None:
from sys import path
from os.path import dirname as dir
path.append(dir(path[0]))
__package__ ...
App restarts rather than resumes
...l Activity. If those two flags are present and the Activity is not at the root of the task (meaning the app was already running), then I call finish() on the initial Activity. That exact solution may not work for you, but something similar should.
Here is what I do in onCreate() of the initial/l...