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Primary key or Unique index?
...hen it tries to insert the value 1 into this column for a second time.
In MySQL a unique constraint allows multiple NULLs.
It is possible to make a unique index on mutiple columns.
Primary key versus unique index
Things that are the same:
A primary key implies a unique index.
Things that are...
What are the various “Build action” settings in Visual Studio project properties and what do they do
....g.resources), Additionally, if you have the appropriate attributes on the root XAML element in the file, it will create a blah.g.cs file, which will contain a partial class of the "codebehind" for that page; this basically involves a call to the BAML goop to re-hydrate the file into memory, and to ...
How do you use https / SSL on localhost?
...-spc localhost.spc -pfx localhost.pfx
2.) Import certificate to Trusted Root Certification Authorities store:
start --> run --> mmc.exe --> Certificates plugin -->
"Trusted Root Certification Authorities" --> Certificates
Right-click Certificates --> All Tasks --> Import...
Custom ListView click issue on items in Android
... should set the descendantFocusability value to 'blocksDescendants' in the root list item element.
android:descendantFocusability="blocksDescendants"
And the focusableInTouchMode flag to true in the ImageButton view.
android:focusableInTouchMode="true"
...
Visual Studio TFS shows unchanged files in the list of pending changes
... away, the command is tfpt uu /noget /r *, which must be executed from the root of the branch. Saying this, although it correctly picks up redundant changes, then claims to undo them, I still see them as checked out in VS and in the Check In dialog, so it seems broken for me :/
...
Share cookie between subdomain and domain
...ript demonstrates that in (say) Chrome, the cookies are not shared between root and subdomains when no domain is specified. However the same test in IE shows that they are shared. This IE case is closer to the take-home description in CMBuckley's www-or-not-www link. I know this to be the case becau...
SELECT * WHERE NOT EXISTS
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How can I edit a view using phpMyAdmin 3.2.4?
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What is the most efficient way of finding all the factors of a number in Python?
...s will return all of the factors, very quickly, of a number n.
Why square root as the upper limit?
sqrt(x) * sqrt(x) = x. So if the two factors are the same, they're both the square root. If you make one factor bigger, you have to make the other factor smaller. This means that one of the two will ...
Why doesn't C have unsigned floats?
... log of values < 1, you couldn't solve quadratic equations: x = (-b +/- root (b.b - 4.a.c)) / 2.a, and so on. In fact, it probably wouldn't work for any complex function as these tend to be implemented as polynomial approximations which would use negative values somewhere.
So, unsigned floats ar...