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Rails migration: t.references with alternative name?
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You can do this all in the initial migration/column definition (at least currently in Rails 5):
t.references :transferable_as, index: true, foreign_key: {to_table: :courses}
t.references :same_as, index: true, foreign_key: {to_table: :courses}
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Fetch the row which has the Max value for a column
...cle allows multiple columns to be matched in an IN clause, which should at least avoid the options that use a correlated subquery, which is seldom a good idea.
Something like this, perhaps (can't remember if the column list should be parenthesised or not):
SELECT *
FROM MyTable
WHERE (User, Date)...
How do I get the height and width of the Android Navigation Bar programmatically?
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Actually the navigation bar on tablets (at least Nexus 7) has different size in portrait and landscape so this function should look like this:
private int getNavigationBarHeight(Context context, int orientation) {
Resources resources = context.getResources();
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using extern template (C++11)
... types of templates in multiple compilation units (like I did today)... At least for clang, the only surefire way is to put these template definitions in your header! Be warned!
– Steven Lu
Jul 17 '14 at 3:50
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Creating folders inside a GitHub repository without using Git
...e a new folder from the web interface, but it would require you to have at least one file within the folder when creating it.
When using the normal way of creating new files through the web interface, you can type in the folder into the file name to create the file within that new directory.
For e...
Why not abstract fields?
...ll have to do dynamic dispatch, and hence a method call. Java's design (at least in the early days) was, to some extent, an attempt to be minimalist. That is, the designers tried to avoid adding new features if they could be easily simulated by other features already in the language.
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Which Java Collection should I use?
...d by an array, where the array has a length (called "capacity") that is at least as large as the number of elements (the list's "size"). When size exceeds capacity (when the (capacity + 1)-th element is added), the array is recreated with a new capacity of (new length * 1.5)--this recreation is fast...
Oracle Differences between NVL and Coalesce
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They are not exactly synonyms... At least you can find a difference in the fact that NVL makes an implicit data type casting if the given values are of different types. So for instance, I was getting an error using COALESCE passing it two NULL values (one expli...
converting drawable resource image into bitmap
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I dont think this is right as a general answer — at least not since Android started supporting vector drawables.
– roberto tomás
Mar 24 '16 at 12:52
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Storyboard - refer to ViewController in AppDelegate
...w do we transition back to the original rootViewController after login. At least to my knowledge of iOS 7 and Xcode 5.0.2 - changing the root view controller back will immediate and without animation switch the view hierarchy. The UX team have murdered coders for less.
– lol
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