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How to pull a random record using Django's ORM?
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count = self.aggregate(count=Count('id'))['count']
random_index = randint(0, count - 1)
return self.all()[random_index]
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Storing R.drawable IDs in XML array
...tResources().obtainTypedArray(R.array.random_imgs);
// get resource ID by index
imgs.getResourceId(i, -1)
// or set you ImageView's resource to the id
mImgView1.setImageResource(imgs.getResourceId(i, -1));
// recycle the array
imgs.recycle();
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Picking a random element from a set
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Fast solution for Java using an ArrayList and a HashMap: [element -> index].
Motivation: I needed a set of items with RandomAccess properties, especially to pick a random item from the set (see pollRandom method). Random navigation in a binary tree is not accurate: trees are not perfectly bal...
Keep ignored files out of git status
...or untracked files. If you added files to repository, you can:
git update-index --assume-unchanged <file>
or remove them from repository by
git rm --cached <file>
Edit
This article explains that too
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UICollectionView current visible cell index
...tionViewCell *cell in [self.mainImageCollection visibleCells]) {
NSIndexPath *indexPath = [self.mainImageCollection indexPathForCell:cell];
NSLog(@"%@",indexPath);
}
}
Update to Swift 5:
func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {
for cell in yourCollec...
On duplicate key ignore? [duplicate]
...getting deadlocks, because it will additionally hold Next-Key lock on your indexes. More: dev.mysql.com/doc/refman/5.7/en/…
– Dzmitry Lazerka
Mar 14 '17 at 7:13
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count(*) vs count(column-name) - which is more correct? [duplicate]
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What about count( col ) where col is a primary indexed column ? I thaught indexes help making tasks faster ?
– Stphane
Aug 28 '15 at 13:47
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Get boolean from database using Android and SQLite
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It is:
boolean value = cursor.getInt(boolean_column_index) > 0;
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Using scanner.nextLine() [duplicate]
...;
scanner.useDelimiter("\\n");
System.out.print("Enter an index: ");
int index = scanner.nextInt();
System.out.print("Enter a sentence: ");
String sentence = scanner.next();
System.out.println("\nYour sentence: " + sentence);
System.out.prin...
Responsive web design is working on desktop but not on mobile device
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make sure the production index.html actually includes the tag as well as development index.html
– halafi
Mar 4 '18 at 9:56
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