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Should each and every table have a primary key?
...e link. Thus you ensure that you don't have two or more records describing one link.
Besides the logical consistency issues, most RDBMS engines will benefit from including these fields in a unique index.
And since any primary key involves creating a unique index, you should declare it and get both...
HTML5 best practices; section/header/aside/article elements
... the "best practices". Tags like section/headers/article are new, and everyone has different opinions about when/where you should use these tags. So what do you guys think of the following layout and code?
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Entity Framework vs LINQ to SQL
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This answer is obsolete. Now Linq to SQL supports one2many mapping
– George Lanetz
Dec 29 '15 at 13:18
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Java: Multiple class declarations in one file
...define multiple top level classes in a single file, providing that at most one of these is public (see JLS §7.6 ). See below for example.
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JPA EntityManager: Why use persist() over merge()?
EntityManager.merge() can insert new objects and update existing ones.
15 Answers
15
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MSBUILD : error MSB1008: Only one project can be specified
... know this is an old post, but I feel like I needed to share this with someone :-)
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All possible array initialization syntaxes
... third line must be written as displayed, as array initialization syntax alone is not enough to satisfy the compiler's demands. The fourth could also use inference. So if you're into the whole brevity thing, the above could be written as
var array = new string[2]; // creates array of length 2, defa...
Check if checkbox is checked with jQuery
... value="Bananas" />
</fieldset>
And now the jQuery:
var atLeastOneIsChecked = $('#checkArray:checkbox:checked').length > 0;
//there should be no space between identifier and selector
// or, without the container:
var atLeastOneIsChecked = $('input[name="chk[]"]:checked').length >...
Catching multiple exception types in one catch block
...y to obtain the following functionality, to catch AError and BError in one block:
11 Answers
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Is there any reason for using WebGL instead of 2D Canvas for 2D games/apps?
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Looking at this question from another side:
how does a developer choose one technology over another?
integrates better in their already built system
is easier to use
is faster
has more capabilities or better suits their needs
cost
more platfrom-independant
So I'll discuss the differences betw...