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Computed / calculated / virtual / derived columns in PostgreSQL
...y as column?
The expression (looking like a column) is not included in a SELECT * FROM tbl, though. You always have to list it explicitly.
Can also be supported with a matching expression index - provided the function is IMMUTABLE. Like:
CREATE FUNCTION col(tbl) ... AS ... -- your computed expr...
How to change or add theme to Android Studio?
...
File->Settings->Editor->Colors & Fonts-> In scheme name select Darcula and apply to see a awesome dark background theme editor
Android Studio 3.1.2
File->Settings->Editor->Color Scheme-> In scheme name select Darcula and apply to see a awesome dark background theme e...
Xcode source automatic formatting
...
this shouldn't be selected as the answer. the answer below from @ken is correct
– Ryan Angilly
Feb 8 '13 at 16:44
...
How to migrate/convert from SVN to Mercurial (hg) on windows
...made
much simpler: Start the TortoiseHG
Workbench from the Start menu. Select
File --> Settings. Select Extensions
from the list. Check the 'convert'
checkbox and click OK. That's it! No
need to try to generate the config
file anymore and search it in the file
system. – bgever M...
How to stop creating .DS_Store on Mac? [closed]
I'm developing sites on mac and every time I create some folder (or file in that folder) .DS_Store is created in that folder.
...
Why use the SQL Server 2008 geography data type?
...tance < 500 * 1609.344
orderby distance
select f;
return q1.FirstOrDefault();
}
Then there is a very good reason to use Geography.
Explanation of spatial within Entity Framework.
Updated with Creating High Performance Spatial Databases
As I noted on Noe...
Adding a simple UIAlertView
...d OK
if (buttonIndex == 0) {
// do something here...
}
}
And make sure your delegate conforms to UIAlertViewDelegate protocol:
@interface YourViewController : UIViewController <UIAlertViewDelegate>
...
Disable migrations when running unit tests in Django 1.7
...ailing list:
If makemigrations has not yet been run, the "migrate" command treats
an app as unmigrated, and creates tables directly from the models just
like syncdb did in 1.6. I defined a new settings module just for unit
tests called "settings_test.py", which imports * from the main
se...
How do I test a camera in the iPhone simulator?
... harder than using the simulator. Just build a debug target for the device and leave it attached to the computer.
List of actions that require an actual device:
the actual phone
the camera
the accelerometer
real GPS data
the compass
vibration
push notifications...
...
Toggle button using two image on different state
...k.xml in drawable folder
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<!-- When selected, use grey -->
<item android:drawable="@drawable/selected_image"
android:state_checked="true" />
<...