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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] ...
Is Java really slow?
...ages (if they use standard libraries).
There is no excuse for "slow" Java applications now. Developers and legacy code/libraries are to blame, far more than the language. Also, blame anything 'enterprise.'
In fairness to the "Java is slow" crowd, here are areas where it is still slow (updated for ...
Are there good reasons not to use an ORM? [closed]
During my apprenticeship, I have used NHibernate for some smaller projects which I mostly coded and designed on my own. Now, before starting some bigger project, the discussion arose how to design data access and whether or not to use an ORM layer. As I am still in my apprenticeship and still cons...
class method generates “TypeError: … got multiple values for keyword argument …”
...de:
myfoo.foodo("something")
print
print myfoo
You'll output like:
<__main__.foo object at 0x321c290>
a thong is something
<__main__.foo object at 0x321c290>
You can see that 'thing' has been assigned a reference to the instance 'myfoo' of the class 'foo'. This section of the docs...
Where to find Java JDK Source Code? [closed]
...d page, what to I have do download? The big file jdk-6u21-ea-src-b04-jrl-05_may_2010.jar, 136.48 MB? I already downloaded that one. But doesn't contain the source code.
– Martijn Courteaux
May 24 '10 at 12:06
...
How can I ssh directly to a particular directory?
..., even if ssh has no local tty.
If you don't use -t then no prompt will appear.
If you don't add ; bash then the connection will get closed and return control to your local machine
share
|
impr...
What is JNDI? What is its basic use? When is it used?
... Directory Interface.
What is its basic use?
JNDI allows distributed applications to look up services in an abstract, resource-independent way.
When it is used?
The most common use case is to set up a database connection pool on a Java EE application server. Any application that's deplo...
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...
How do I clone a Django model instance object and save it to the database?
...imary key of your object and run save().
obj = Foo.objects.get(pk=<some_existing_pk>)
obj.pk = None
obj.save()
If you want auto-generated key, set the new key to None.
More on UPDATE/INSERT here.
Official docs on copying model instances: https://docs.djangoproject.com/en/2.2/topics/db/que...