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COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better? [duplicate]
...T(field) or COUNT(*), and stick with it consistently, and if your database allows COUNT(tableHere) or COUNT(tableHere.*), use that.
In short, don't use COUNT(1) for anything. It's a one-trick pony, which rarely does what you want, and in those rare cases is equivalent to count(*)
Use count(*) fo...
Clone() vs Copy constructor- which is recommended in java [duplicate]
...rclass since the
Beta-release days of the Java
compiler*; and it, like all ancient
magic, requires the appropriate
incantation to prevent the spell from
unexpectedly backfiring
Prefer a method that copies the object
Foo copyFoo (Foo foo){
Foo f = new Foo();
//for all properties in F...
How to dismiss a Twitter Bootstrap popover by clicking outside?
...-title]' in place of '[data-toggle="popover"]'
Caveat: The solution above allows multiple popovers to be open at once.
One popover at a time please:
Update: Bootstrap 3.0.x, see code or fiddle http://jsfiddle.net/mattdlockyer/C5GBU/2/
$('body').on('click', function (e) {
$('[data-toggle="pop...
Efficiency of Java “Double Brace Initialization”?
...2$8.class
2009/05/27 16:35 2,022 DemoApp2$9.class
These are all classes which were generated when I was making a simple application, and used copious amounts of anonymous inner classes -- each class will be compiled into a separate class file.
The "double brace initialization", as al...
Map Tiling Algorithm
...
The basic idea of this algorithm is to use a pre-processing step to find all edges and then select the correct smoothing tile according to the shape of the edge.
The first step would be to find all edges. In the example below the edge tiles marked with an X are all green tiles with a tan tile as ...
Python logging not outputting anything
...
@Ben where does it say that? All I can see is "The default level is WARNING, which means that only events of this level and above will be tracked, unless the logging package is configured to do otherwise."
– Omri Barel
...
How do you see recent SVN log entries?
...n the given dates:
svn log -r {2011-02-02}:{2011-02-03}
You can combine all the above expressions with the --limit option, so that can you have a quite granular control over what is printed. For more info about these -r expressions refer to svn help log or the relevant chapter in the book Version...
How can I pretty-print JSON in a shell script?
...ou can use
curl http://my_url/ | python -m json.tool
For convenience in all of these cases you can make an alias:
alias prettyjson='python -m json.tool'
For even more convenience with a bit more typing to get it ready:
prettyjson_s() {
echo "$1" | python -m json.tool
}
prettyjson_f() {...
Rebuild or regenerate 'ic_launcher.png' from images in Android Studio
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Beware using Asset Studio in Android Studio automatically adds padding, shrinking the resulting image.
– Androidcoder
Jun 16 '15 at 17:03
...
What is the difference between DAO and Repository patterns?
...ing DAO's, but you wouldn't do the opposite.
Also, a Repository is generally a narrower interface. It should be simply a collection of objects, with a Get(id), Find(ISpecification), Add(Entity).
A method like Update is appropriate on a DAO, but not a Repository - when using a Repository, chan...