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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...
What is your naming convention for stored procedures? [closed]
...ow the database is at 700 procedures plus, it becomes a lot harder to find all procedures on a specific object. For example i now have to search 50 odd Add procedures for the Product add, and 50 odd for the Get etc.
Because of this in my new application I'm planning on grouping procedure names by o...
How to add a custom loglevel to Python's logging facility
...for my application, as I don't think that debug() is sufficient. Additionally log(5, msg) isn't what I want. How can I add a custom loglevel to a Python logger?
...
How to sum array of numbers in Ruby?
... using array.map(...).inject(...) is inefficient, you will iterate through all data twice. Try array.inject(0) { |sum, product| sum += product.price }
– everett1992
Apr 4 '13 at 6:11
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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...
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
...
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 create a file in memory for user to download, but not through server?
...h the server?
I know I can't write directly to their machine (security and all), but can I create and prompt them to save it?
...
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.
...
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...