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Can an html element have multiple ids?
...ec is very clear about this:
If an element has multiple ID attributes, all of them must be treated as IDs for that element for the purposes of the ID selector.Such a situation could be reached using mixtures of xml:id, DOM3 Core, XML DTDs, and namespace-specific knowledge.
Edit
Just to clar...
C++11 std::threads vs posix threads
...gcc std::thread is perfectly fine - it has a higher abstraction level, a really good interface and plays nicely with other C++11 classes.
The C++11 std::thread class unfortunately doesn't work reliably (yet) on every platform, even if C++11 seems available. For instance in native Android std::threa...
Singletons vs. Application Context in Android?
Recalling this post enumerating several problems of using singletons
and having seen several examples of Android applications using singleton pattern, I wonder if it's a good idea to use Singletons instead of single instances shared through global application state (subclassing android.os.Applicat...
OpenLayers vs Google Maps? [closed]
...
These are a really great questions! I'm a professional OpenLayers developer and fan, so I'll address your questions from that perspective.
Why would I use OpenLayers instead of Google Maps?
Flexiblity: You are not tied to any particular...
JavaScript checking for null vs. undefined and difference between == and ===
...is the difference between the null and undefined?
They're both values usually used to indicate the absence of something. undefined is the more generic one, used as the default value of variables until they're assigned some other value, as the value of function arguments that weren't provided when ...
JavaScript naming conventions [closed]
... the first letter, or the entire acronym be lowercased? Example: ECBhandle vs. ecbHandle (it does not matter what ECB means).
– Dan Dascalescu
Dec 4 '13 at 12:37
13
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When to use PNG or JPG in iPhone development?
...more compressed image formats, and thus be slower to display.
JPG's are smaller to store, but lossy (amount depends on compression level), and to display them requires a much more complicated decoding algorithm. But the typical compression and image quality is usually quite sufficient for photos.
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SQL - HAVING vs. WHERE
...erage, min, max, or sum, has been produced from multiple rows. Your query calls for a second kind of condition (i.e. a condition on an aggregation) hence HAVING works correctly.
As a rule of thumb, use WHERE before GROUP BY and HAVING after GROUP BY. It is a rather primitive rule, but it is useful ...
Single huge .css file vs. multiple smaller specific .css files? [closed]
... to deliver a single, minimised CSS file for the site (which will be far smaller and faster than a normal single CSS source file), while maintaining the nicest development environment, with everything neatly split into components.
Sass and LESS have the added advantage of variables, nesting and oth...
Optimistic vs. Pessimistic locking
...to the database for your session. In this situation the client cannot actually maintain database locks as the connections are taken from a pool and you may not be using the same connection from one access to the next.
Pessimistic Locking is when you lock the record for your exclusive use until you...