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What's the difference(s) between .ToList(), .AsEnumerable(), AsQueryable()?
...or example, we need to use one of our own methods in a query we would typically write something like
var query = context.Observations.Select(o => o.Id)
.AsEnumerable().Select(x => MySuperSmartMethod(x))
ToList – which converts an IEnumerable<T> to a List<T> ...
Conditionally start at different places in storyboard from AppDelegate
...ful, and show the login view controller if the authentication failed.
Basically, I want to do this in my AppDelegate:
10 An...
When to use “ON UPDATE CASCADE”
...ange it to a 13-digit UPC bar code. In that case, ON UPDATE CASCADE would allow you to change the primary key value and any tables that have foreign key references to the value will be changed accordingly.
In reference to #4, if you change the child ID to something that doesn't exist in the parent...
How do I compute derivative using Numpy?
...rivative of y wrt x. In 8 we apply this derivative function to a vector of all ones and get the vector of all twos. This is because, as stated in line 6, yprime = 2*x.
– MRocklin
Apr 14 '12 at 13:45
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Differences between Proxy and Decorator Pattern
...ll start off with an indirect reference such as a file name but will eventually
obtain and use a direct reference.
Popular answers indicate that a Proxy knows the concrete type of its delegate. From this quote we can see that is not always true.
The difference between Proxy and Decorator accord...
git merge: apply changes to code that moved to a different file
...s copy has been done in a commit that we name commit CP.
You want to apply all your local changes, commits A and B below, that were made on original.txt, to the new file copy.txt.
---- X -----CP------ (master)
\
`--A---B--- (local)
Create a throwaway branch move at the starting p...
Can I split an already split hunk with git?
... discovered git's patch option to the add command, and I must say it really is a fantastic feature.
I also discovered that a large hunk could be split into smaller hunks by hitting the s key, which adds to the precision of the commit.
But what if I want even more precision, if the split hunk i...
SQL Query Where Field DOES NOT Contain $x
...hing a string, go for the LIKE operator (but this will be slow):
-- Finds all rows where a does not contain "text"
SELECT * FROM x WHERE x.a NOT LIKE '%text%';
If you restrict it so that the string you are searching for has to start with the given string, it can use indices (if there is an index ...
How do I resolve “Cannot find module” error using Node.js?
...
Using npm install installs the module into the current directory only (in a subdirectory called node_modules). Is app.js located under home/dave/src/server/? If not and you want to use the module from any directory, you need to install i...
iOS: Modal ViewController with transparent background
I'm trying to present a view controller modally, with a transparent background. My goal is to let both the presenting and presented view controllers's view to be displayed at the same time. The problem is, when the presenting animation finishes, the presenting view controller's view disappears.
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