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what is the difference between GROUP BY and ORDER BY in sql
...
They have totally different meaning and aren't really related at all.
ORDER BY allows you to sort the result set according to different criteria, such as first sort by name from a-z, then sort by the price highest to lowest.
(ORDER BY name, price DESC...
How to handle Objective-C protocols that contain properties?
...at objects holding references to them can use them in specific ways.
That means in your class that conforms to your protocol, you have to do everything to make sure anObject works.
@property and @synthesize are at heart two mechanisms that generate code for you. @property is just saying there w...
ASP.NET MVC - Set custom IIdentity or IPrincipal
... how I do it.
I decided to use IPrincipal instead of IIdentity because it means I don't have to implement both IIdentity and IPrincipal.
Create the interface
interface ICustomPrincipal : IPrincipal
{
int Id { get; set; }
string FirstName { get; set; }
string LastName { get; set; }
}
...
What does git push -u mean?
...tps%3a%2f%2fstackoverflow.com%2fquestions%2f5561295%2fwhat-does-git-push-u-mean%23new-answer', 'question_page');
}
);
Post as a guest
Name
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java: HashMap not working
...h auto-boxing/unboxing there is little difference in the code. Auto-boxing means you can write:
myMap.put("foo", 3);
instead of:
myMap.put("foo", new Integer(3));
Auto-boxing means the first version is implicitly converted to the second. Auto-unboxing means you can write:
int i = myMap.get("f...
Is Redis just a cache?
...ta structure server.
Being a cache in the form of a data structure server means a lot, because data structures are fundamentals of programs, or applications. Consider you are using SQL databases as storage technology and need to construct a list, a hash map, a ranking set or things like that, it's ...
How to make an anchor tag refer to nothing?
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breaks when linking images in IE What does this mean?
– eugene
Aug 30 '13 at 3:44
15
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ASP.Net MVC: How to display a byte array image from model
... and if you don't have too many of them, and if the images are not secret (meaning it's no big deal if one user could potentially see another person's image)...
Lots of "if"s here, so there's a good chance this is a bad idea:
You can store the image bytes in Cache for a short time, and make an ima...
How to design a product table for many kinds of product where each product has many parameters
...uct types, with enough columns to store all attributes of all types. This means a lot of columns, most of which are NULL on any given row.
Class Table Inheritance: one table for Products, storing attributes common to all product types. Then one table per product type, storing attributes specific t...
When to use symbols instead of strings in Ruby?
...as identifiers in your code. You should be worrying about what symbols are meant to be, not only when you should use symbols. Symbols are meant to be identifiers. If you follow this philosophy, chances are that you will do things right.
There are several differences between the implementation of s...