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SQL Server 2005 How Create a Unique Constraint?
... you want to do it from a Database Diagram:
right-click on the table and select 'Indexes/Keys'
click the Add button to add a new index
enter the necessary info in the Properties on the right hand side:
the columns you want (click the ellipsis button to select)
set Is Unique to Yes
give it an app...
C++ mark as deprecated
...erface that I want to deprecate with portable C++.
When I Googled for this all I got was a Microsoft specific solution; #pragma deprecated and __declspec(deprecated) .
...
Enums and Constants. Which to use when?
...ype. You can change the default from int to any other integral type except char like:
enum LongEnum : long {
foo,
bar,
}
You can cast explicitly from and implicitly to the the base type, which is useful in switch-statements. Beware that one can cast any value of the base type to an enum, ...
Using python's eval() vs. ast.literal_eval()?
...
datamap = eval(raw_input('Provide some data here: ')) means that you actually evaluate the code before you deem it to be unsafe or not. It evaluates the code as soon as the function is called. See also the dangers of eval.
ast.literal_eval raises an exception if the input isn't a valid Python dat...
Do try/catch blocks hurt performance when exceptions are not thrown?
... {
Console.WriteLine(ex.ToString());
}
finally
{
d = Math.Sin(d);
}
}
w.Stop();
Console.Write(" try/catch/finally: ");
Console.WriteLine(w.ElapsedMilliseconds);
w.Reset();
d = 0;
w.Start();
for (int i = ...
How do I get the result of a command in a variable in windows?
...
If you have to capture all the command output you can use a batch like this:
@ECHO OFF
IF NOT "%1"=="" GOTO ADDV
SET VAR=
FOR /F %%I IN ('DIR *.TXT /B /O:D') DO CALL %0 %%I
SET VAR
GOTO END
:ADDV
SET VAR=%VAR%!%1
:END
All output lines are stor...
How do I add a placeholder on a CharField in Django?
...
Look at the widgets documentation. Basically it would look like:
q = forms.CharField(label='search',
widget=forms.TextInput(attrs={'placeholder': 'Search'}))
More writing, yes, but the separation allows for better abstraction of more complic...
How do I show an open file in eclipse Package Explorer?
...oices. The choices will vary depending on what plugins you have installed. Select the option you want and press Enter.
The fastest way to select an option is to use the first letter of the option, eg. to go to the Package Explorer, press P (you may have to do this 2 or 3 times depending on how many...
Why can't I overload constructors in PHP?
I have abandoned all hope of ever being able to overload my constructors in PHP, so what I'd really like to know is why .
...
Hashing a dictionary?
...e hash():
hash(frozenset(my_dict.items()))
This is much less computationally intensive than generating the JSON string or representation of the dictionary.
UPDATE: Please see the comments below, why this approach might not produce a stable result.
...