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How do I get SUM function in MySQL to return '0' if no values are found?
...iddle.com/#!2/d1542/3/0
More Information:
Given three tables (one with all numbers, one with all nulls, and one with a mixture):
SQL Fiddle
MySQL 5.5.32 Schema Setup:
CREATE TABLE foo
(
id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
val INT
);
INSERT INTO foo (val) VALUES
(null),(1),(n...
Why should we typedef a struct so often in C?
...As Greg Hewgill said, the typedef means you no longer have to write struct all over the place. That not only saves keystrokes, it also can make the code cleaner since it provides a smidgen more abstraction.
Stuff like
typedef struct {
int x, y;
} Point;
Point point_new(int x, int y)
{
Point a...
How to select option in drop down protractorjs e2e tests
...
I had a similar problem, and eventually wrote a helper function that selects dropdown values.
I eventually decided that I was fine selecting by option number, and therefore wrote a method that takes an element and the optionNumber, and selects that optionNumb...
Where is Java's Array indexOf?
I must be missing something very obvious, but I've searched all over and can't find this method.
13 Answers
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How to properly add include directories with CMake
...the headers... Do I need to list the headers of just this library, or also all the headers that it might depend on (on top of declaring the dependency on the library) ? It's a growing project and I quite dread the idea of adding a header to all the dependencies when I add one in the root library.
...
CruiseControl [.Net] vs TeamCity for continuous integration?
...ince the one that spawned Cruise Control (java version). I've tried almost all of them at some point. I've never been happier than I am with TeamCity. It is very simple to set up and still provides a great deal of power. The build statistics page that shows build times, unit test count, pass rate et...
Conventions for exceptions or error codes
...ary it's probably an error, and I want the program to halt and let me know all about that.
If, however, I'm writing a piece of code which I must know the behaviour of in every possible situation, then I want error codes. Otherwise I have to know every exception that can be thrown by every line in ...
Why are global variables evil? [closed]
...ad in any programming language.
However, global constants are not conceptually the same as global variables; global constants are perfectly harmless. In Python the distinction between the two is purely by convention: CONSTANTS_ARE_CAPITALIZED and globals_are_not.
The reason global variables are ba...
Internet Explorer 9 not rendering table cells properly
...umns outside the boundries of my table.
I fixed this by doing something really silly; removing all the spaces betwen the <td> start and end tags and left justifying the HTML markup pertaining to my table. Basically, you want all of your <td> </td> on the same line, no spaces.
Exa...
How to initialize all members of an array to the same value in Swift?
I have a large array in Swift. I want to initialize all members to the same value (i.e. it could be zero or some other value). What would be the best approach?
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