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Unique constraint on multiple columns
...le columns. The syntax, simplified 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,...
Mixins vs. Traits
... a year past date, but for future readers, in ruby it would use the method form the last module that was mixed in, so it would call foo() form MB
– rik.vanmechelen
Jan 12 '12 at 19:36
...
What's a concise way to check that environment variables are set in a Unix shell script?
...
Parameter Expansion
The obvious answer is to use one of the special forms of parameter expansion:
: ${STATE?"Need to set STATE"}
: ${DEST:?"Need to set DEST non-empty"}
Or, better (see section on 'Position of double quotes' below):
: "${STATE?Need to set STATE}"
: "${DEST:?Need to set DEST n...
What is the difference between and ?
...e <p> for "paragraph of content", does the content have to be in the form of letters and words? Would you ever use <p> to describe some other type of content, like images?
– drs
Jun 11 '13 at 11:42
...
What are the primary differences between TDD and BDD? [closed]
...ein'
When the user logs in with username and password
Then the login form should be shown again
(In his article, Tom goes on to directly execute this test specification in Ruby.)
The pope of BDD is Dan North. You'll find a great introduction in his Introducing BDD article.
You will find a ...
How do I get the MAX row with a GROUP BY in LINQ query?
...
In methods chain form:
db.Serials.GroupBy(i => i.Serial_Number).Select(g => new
{
Serial_Number = g.Key,
uid = g.Max(row => row.uid)
});
...
Ways to iterate over a list in Java
...
The three forms of looping are nearly identical. The enhanced for loop:
for (E element : list) {
. . .
}
is, according to the Java Language Specification, identical in effect to the explicit use of an iterator with a traditional...
What is the difference between the hidden attribute (HTML5) and the display:none rule (CSS)?
...kind of overflow presentation — one could equally well just show all the form controls in one big page with a scrollbar. It is similarly incorrect to use this attribute to hide content just from one presentation — if something is marked hidden, it is hidden from all presentations, including, for...
is not JSON serializable
...t_queryset() and replace them with dicts using model_to_dict:
from django.forms.models import model_to_dict
data = self.get_queryset()
for item in data:
item['product'] = model_to_dict(item['product'])
return HttpResponse(json.simplejson.dumps(data), mimetype="application/json")
Hope that h...
What are the nuances of scope prototypal / prototypical inheritance in AngularJS?
...nce is normally straightfoward... until you need 2-way data binding (i.e., form elements, ng-model) in the child scope. Ng-repeat, ng-switch, and ng-include can trip you up if you try to bind to a primitive (e.g., number, string, boolean) in the parent scope from inside the child scope. It doesn't...