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postgresql return 0 if returned value is null
...ns the first of its arguments that is not null.
Null is returned only if all arguments are null. It is often
used to substitute a default value for null values when data is
retrieved for display.
Edit
Here's an example of COALESCE with your query:
SELECT AVG( price )
FROM(
SELECT *, cum...
Why do we use $rootScope.$broadcast in AngularJS?
... scope of that app can catch it using a simple: $scope.$on().
It is especially useful to send events when you want to reach a scope that is not a direct parent (A branch of a parent for example)
!!! One thing to not do however is to use $rootScope.$on from a controller. $rootScope is the applicati...
List files in local git repo?
...
This command:
git ls-tree --full-tree -r --name-only HEAD
lists all of the already committed files being tracked by your git repo.
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Memcache(d) vs. Varnish for speeding up 3 tier web architecture
...ache will provide info for pages that have a mixture of known and new data allowing you to generate pages faster.
An example that could apply to stackoverflow.com: adding this comment invalidated the page cache, so this page would have to be cleared from Varnish (and also my profile page, which pr...
git -> show list of files changed in recent commits in a specific directory
...n. If you need a comprehensive list of commits, try making the number unusually large, like -1000 or more as needed.
– Julian Soro
Jan 8 '15 at 20:07
...
Redis strings vs Redis hashes to represent JSON: efficiency?
I want to store a JSON payload into redis. There's really 2 ways I can do this:
3 Answers
...
Solving “Who owns the Zebra” programmatically?
...ution in Python based on constraint-programming:
from constraint import AllDifferentConstraint, InSetConstraint, Problem
# variables
colors = "blue red green white yellow".split()
nationalities = "Norwegian German Dane Swede English".split()
pets = "birds dog cats horse zebra".sp...
Why is an int in OCaml only 31 bits?
...
This is called a tagged pointer representation, and is a pretty common optimization trick used in many different interpreters, VMs and runtime systems for decades. Pretty much every Lisp implementation uses them, many Smalltalk VMs, m...
Setting onClickListener for the Drawable right of an EditText [duplicate]
... y = actionY;
/** Creates square from the smallest value */
if (x < y) {
y = x;
}
}
if (bounds.contains(x, y) && clickListener != null) {
cli...
Using CSS to insert text
...
It is, but requires a CSS2 capable browser (all major browsers, IE8+).
.OwnerJoe:before {
content: "Joe's Task:";
}
But I would rather recommend using Javascript for this. With jQuery:
$('.OwnerJoe').each(function() {
$(this).before($('<span>').text("Joe'...