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Unique constraint on multiple columns
...ied from technet's documentation, is in the form of:
CONSTRAINT constraint_name UNIQUE [ CLUSTERED | NONCLUSTERED ]
(
column [ ASC | DESC ] [ ,...n ]
)
Therefore, the resuting table definition would be:
CREATE TABLE [dbo].[user](
[userID] [int] IDENTITY(1,1) NOT NULL,
[fcode] [int] ...
How to perform Callbacks in Objective-C
...newer) option is to use blocks:
@interface MyClass: NSObject
{
void (^_completionHandler)(int someParameter);
}
- (void) doSomethingWithCompletionHandler:(void(^)(int))handler;
@end
@implementation MyClass
- (void) doSomethingWithCompletionHandler:(void(^)(int))handler
{
// NOTE: copyin...
Read only the first line of a file?
...od (Python 2 docs, Python 3 docs):
with open('myfile.txt') as f:
first_line = f.readline()
Some notes:
As noted in the docs, unless it is the only line in the file, the string returned from f.readline() will contain a trailing newline. You may wish to use f.readline().strip() instead to rem...
URLs: Dash vs. Underscore [closed]
...
Reasonable guess, but as it turns out, totally untrue. -1.
– Mark Amery
Feb 4 '15 at 23:29
...
Windows 7 SDK installation failure
I seem to be completely unable to install the Windows 7 SDK onto my machine, and the only solution I've found on the web is to make a swathe of registry changes. I've done this - still no success.
...
Async image loading from url inside a UITableView cell - image changes to wrong image while scrollin
...se you'll see the flickering of images.
A more subtle issue is that on a really slow network, your asynchronous request might not finish before the cell scrolls off the screen. You can use the UITableView method cellForRowAtIndexPath: (not to be confused with the similarly named UITableViewDataSourc...
Cloning an Object in Node.js
...ion is now marked as deprecated in the documentation of Node.js:
The util._extend() method was never intended to be used outside of internal Node.js modules. The community found and used it anyway.
It is deprecated and should not be used in new code. JavaScript comes with very similar built-in func...
JavaScript, elegant way to check nested object properties for null/undefined [duplicate]
...e of using the app this gets populated. Let's say somwhere, after an AJAX call or something i do this:
4 Answers
...
What exactly are DLL files, and how do they work?
... files, ...) that an EXE, or other DLL uses.
Types of libraries:
On virtually all operating systems, there are 2 types of libraries. Static libraries and dynamic libraries. In windows the file extensions are as follows: Static libraries (.lib) and dynamic libraries (.dll). The main difference i...
Detect the specific iPhone/iPod touch model [duplicate]
...on 4,4s,and 5, but it failed hard in production and didn't seem to work at all which caused lots of problems.
– Dave Chenell
May 7 '13 at 2:24
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