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What's wrong with nullable columns in composite primary keys?
...l relationship.(*) Allowing it in the PK as well would break this.
(*)A word of caution: Having nullable foreign keys is not clean relational database design.
If there are two entities A and B where A can optionally be related to B, the clean solution is to create a resolution table (let's say A...
What is Unicode, UTF-8, UTF-16?
...hen dealing with large amounts of text, such as large web-pages or lengthy word documents, this could impact performance.
Encoding basics
Note: If you know how UTF-8 and UTF-16 are encoded, skip to the next section for practical applications.
UTF-8: For the standard ASCII (0-127) characters, the...
Is there a difference between copy initialization and direct initialization?
...n is allowed to omit the copy construction of a class object ...
In other words, a good compiler will not create a copy for copy-initialization when it can be avoided; instead it will just call the constructor directly -- ie, just like for direct-initialization.
In other words, copy-initialization...
What is the difference between properties and attributes in HTML?
...L properties and attributes:
Let's first look at the definitions of these words before evaluating what the difference is in HTML:
English definition:
Attributes are referring to additional information of an object.
Properties are describing the characteristics of an object.
In HTML context:
W...
What is the difference between i++ and ++i?
... knowledge, but for the average C# application, the difference between the wording in the other answers and the actual stuff going on is so far below the abstraction level of the language that it really makes no difference. C# is not assembler, and out of 99.9% of the times i++ or ++i are used in co...
What exactly is Hot Module Replacement in Webpack?
...s quite long so here is a GIF image that explains the concept without much words.
Here it is at work – notice that the timer doesn’t reset to 0 as it would after a page reload, and css changes auto refresh too.
Webpack helps to acheive HMR. You can find docs here
It helps to achieve the followi...
Difference between a “coroutine” and a “thread”?
...mer and programming language determine when to switch coroutines; in other words, tasks are cooperatively multitasked by pausing and resuming functions at set points, typically (but not necessarily) within a single thread.
Long answer: In contrast to threads, which are pre-emptively scheduled by th...
What's the difference between EscapeUriString and EscapeDataString?
...the query string without regard for escaping:
http://example.org/?key=two words
Uri.EscapeUriString will (correctly) escape the space for you:
http://example.org/?key=two%20words
You decide to manually edit the query string even further:
http://example.org/?parameter=father&son
How...
What does it mean to hydrate an object?
...ooked into it.
As best as I can tell, I don't think this project used the word "hydrate" in a very generic sense. I see its use in the title as an approximate synonym for "serialization". As explained above, this usage isn't entirely accurate:
See: http://en.wikipedia.org/wiki/Serialization
tr...
Why is lock(this) {…} bad?
...k involves cache-flush CPU operations and is somewhat expensive. In other words: do not lock and update each individual integer. :)
– Zan Lynx
Oct 31 '08 at 0:12
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