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Add unique constraint to combination of two columns
...ctive, PersonNumber)
VALUES(N'foo', 1, 22);
GO
Data in the table after all of this:
ID Name Active PersonNumber
---- ------ ------ ------------
1 foo 1 22
2 foo 0 22
Error message on the last insert:
Msg 2627, Level 14, State 1, Line 3
Violation of UNIQUE KEY c...
Why is exception handling bad?
...anguage has no exceptions as a design choice, and Linus of Linux fame has called exceptions crap. Why?
15 Answers
...
Increment a database field by 1
...r perhaps you're looking for something like INSERT...MAX(logins)+1? Essentially you'd run a query much like the following - perhaps a bit more complex depending on your specific needs:
INSERT into mytable (logins)
SELECT max(logins) + 1
FROM mytable
...
How to get Core Data object from specific Object ID?
...fault object with the provided objectID, whether or not such an object actually exists in the store. If it doesn't exist, anything that fires the fault will fail unless you insert the object first with NSManagedObjectContext's insertObject:. The only use I've found for this is copying objects from s...
Remove all special characters except space from a string using JavaScript
I want to remove all special characters except space from a string using JavaScript.
11 Answers
...
Using scanf() in C++ programs is faster than using cin?
...mple case: a program to read a list of numbers from standard input and XOR all of the numbers.
iostream version:
#include <iostream>
int main(int argc, char **argv) {
int parity = 0;
int x;
while (std::cin >> x)
parity ^= x;
std::cout << parity << std::endl;
...
What is a StoryBoard ID and how can i use this?
...ould be from any ViewController:
//Maybe make a button that when clicked calls this method
- (IBAction)buttonPressed:(id)sender
{
MyCustomViewController *vc = [self.storyboard instantiateViewControllerWithIdentifier:@"MyViewController"];
[self presentViewController:vc animated:YES completi...
Find unmerged Git branches?
...
The below script will find all origin/* branches that are ahead of current branch
#!/bin/bash
CURRENT_BRANCH=$(git rev-parse --abbrev-ref HEAD)
echo -e "Current branch: \e[94m$CURRENT_BRANCH\e[0m"
echo ''
git branch -a | grep remotes/origin/ | whil...
Emulating a do-while loop in Bash
...ing different, only that true is not a built-in in Bash. It's a program usually found in /bin.
– Fleshgrinder
Feb 12 at 22:07
1
...
How to decide font color in white or black depending on background color?
... have the intensities for the individual colors, you can determine the overall intensity of the color and choose the corresponding text.
if (red*0.299 + green*0.587 + blue*0.114) > 186 use #000000 else use #ffffff
The threshold of 186 is based on theory, but can be adjusted to taste. Based on ...