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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...
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...
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 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...
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 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?
...
Eclipse - debugger doesn't stop at breakpoint
...en released against 6u16, 6u18 and 7b1). The best bet is to use -XX:+UseParallelGC flag. Increasing the size of the minimum and maximum heap size, to delay the first GC, bring temporary relief.
By the way, use this bug report in Eclipse to track how others have been faring.
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Are members of a C++ struct initialized to 0 by default?
...hot s; // receives no initialization
Snapshot s = {}; // value initializes all members
The second will make all members zero, the first leaves them at unspecified values. Note that it is recursive:
struct Parent { Snapshot s; };
Parent p; // receives no initialization
Parent p = {}; // value init...