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Entity Framework 4 Single() vs First() vs FirstOrDefault()
...turned by a query but you only want to access the first item in your code (ordering could be important in the query here). This will throw an exception if the query does not return at least one item.
FirstOrDefault() - when you expect zero or more items to be returned by a query but you only want to...
Can hash tables really be O(1)?
...for use in a dictionary does not have to look at every bit in the input in order to calculate the hash. Implementations are free to look at only a fixed number of bits.
For sufficiently many items the number of items will become greater than the number of possible hashes and then you will get colli...
Difference between binary tree and binary search tree
...nition ahead) each point to a binary tree.
A binary search tree (BST) or "ordered binary tree" is a type of binary tree where the nodes are arranged in order: for each node, all elements in its left subtree are less to the node (<), and all the elements in its right subtree are greater than the ...
what is Promotional and Feature graphic in Android Market/Play Store?
...s not required to save and publish your Store Listing, it is
required in order to be featured on Google Play.
Commentary:
To be clear, these "promotions" are chosen at Google's discretion. Even though excellent the "This is a test" app demonstration (above) shows the Feature graphic used in com...
Presenting a UIAlertController properly on an iPad using iOS 8
...here
}];
// note: you can control the order buttons are shown, unlike UIActionSheet
[alertController addAction:destroyAction];
[alertController addAction:otherAction];
[alertController setModalPresentationStyle:UIModalPresentationPopover];
UIPopoverPresentationC...
Why compile Python code?
...ete and whatever benefits you gained are lost. You need to recompile it in order to get the .pyc or .pyo benefits back again again, such as they may be.
Drawbacks:
First: There's a "magic cookie" in .pyc and .pyo files that indicates the system architecture that the python file was compiled in. If...
Make div stay at bottom of page's content all the time even when there are scrollbars
...ht : 100%' to the main generated FORM tag as well as HTML and BODY tags in order for this to work.
– msouth
May 28 '15 at 14:38
...
Multiprocessing - Pipe vs Queue
...nd nice that you provided benchmarks! I only have two tiny quibbles: (1) "orders of magnitude faster" is a bit of an overstatement. The difference is x3, which is about a third of one order of magnitude. Just saying. ;-); and (2) a more fair comparison would be running N workers, each communicati...
Javascript reduce() on Object
... reduce is an Array method, not an Object's one, and you can't rely on the order when you're iterating the properties of an object (see: https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Statements/for...in, this is applied to Object.keys too); so I'm not sure if applying reduce over an ...
Opacity CSS not working in IE8
...
Correct, but: "In order to guarantee that users of both Internet Explorer 7 and 8 experience the filter, you can include both syntaxes listed above. Due to a peculiarity in our parser, you need to include the updated syntax first before the ol...