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MySQL indexes - what are the best practices?
...lue "M" in the third column. Given what you have available, you have only one option. You scan the table checking the value of the third column for each row. If you've got a lot of rows, this method (a "table scan") can take a long time!
Now imagine that in addition to this table, you've got an ...
How to write a switch statement in Ruby
...
It is done using case in Ruby. Also see "Switch statement" on Wikipedia.
Quoted:
case n
when 0
puts 'You typed zero'
when 1, 9
puts 'n is a perfect square'
when 2
puts 'n is a prime number'
puts 'n is an even number'
when ...
static constructors in C++? I need to initialize private static objects
... thanks! though that's very annoying to have to do all that. One of the many "mistakes" C# and java learned from.
– Gordon Gustafson
Jul 28 '09 at 22:59
110
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AngularJs: How to check for changes in file input fields?
...our File</button>
<input type="file" style="display:none"
id="file" name='file' onchange="angular.element(this).scope().fileNameChanged(this)" />
</form>
</div>
instead of
<input type="file" style="display:none"
id="fil...
How to change background color in android app
... This is the right answer because it has themes, I believe. A one-liner is NOT the simplest way, but a way to spread an entire style to everything is. Styles are how you achieve one-line with even complex changes. Also, styles work on preferences, unlike general attributes. (although st...
How can I disable ARC for a single file in a project?
...e 4, in build phases, and compile sources, there are actually two columns. One for the file name, and another for the compile flags for that one file. This is where you enter this specific compiler flag.
– casademora
Jul 26 '11 at 17:58
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Sequelize.js delete query?
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For anyone using Sequelize version 3 and above, use:
Model.destroy({
where: {
// criteria
}
})
Sequelize Documentation - Sequelize Tutorial
...
What are static factory methods?
...s to provide a "spare" connection, failing with an exception if there are none.
public class DbConnection{
private static final int MAX_CONNS = 100;
private static int totalConnections = 0;
private static Set<DbConnection> availableConnections = new HashSet<DbConnection>();
...
How to compare objects by multiple fields
...a of using a single Comparator. I don't think this answer is wrong, but anyone reading it should definitely check Steve Kuo answer below.
– Felipe Leão
Nov 13 '14 at 12:15
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Renaming a virtualenv folder without breaking it
...e | grep -v "^Binary file" | grep -i venv-name. In fact, I noticed that in one of my Django instances, a lot of the packages had the "path to Python sh-bang" in them.
– Kevin
May 23 '16 at 14:01
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