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When to use Hadoop, HBase, Hive and Pig?
...do with it. That said, you can efficiently put or fetch data to/from HBase by writing MapReduce jobs. Alternatively you can write sequential programs using other HBase APIs, such as Java, to put or fetch the data. But we use Hadoop, HBase etc to deal with gigantic amounts of data, so that doesn't ma...
Forward declaring an enum in C++
... The size of a reference or pointer to a class object is set by the compiler, and independent of the actual size of the object - it is the size of pointers and references. The enum is an object, and its size is needed for the compiler to access the correct storage.
...
Finding what branch a Git commit came from
...eflogs for the line for that commit. Reflogs older than 90 days are pruned by git-gc, so if the commit's too old, you won't find it. That said, you can do this:
git reflog show --all | grep a871742
to find commit a871742. Note that you MUST use the abbreviatd 7 first digits of the commit. The ou...
Encrypting & Decrypting a String in C# [duplicate]
...ijndaelManaged class does indeed normally require you to "muck about" with byte arrays, salts, keys, initialization vectors etc. but this is precisely the kind of detail that can be somewhat abstracted away within your "wrapper" class.
The following class is one I wrote a while ago to perform exact...
Declare a const array
...ight not be the most efficient solution.
But if you re-use the same array (by putting it in a private attribute for instance) it will again open up the possibility to change the contents of the array.
If you want to have an immutable array (or list) you could also use:
public static IReadOnlyList&...
Resolving a Git conflict with binary files
...y autocommits after merging, but when it detects conflicts it cannot solve by itself, it applies all patches it figured out and leaves the rest for you to resolve and commit manually. The Git Merge Man Page, the Git-SVN Crash Course or this blog entry might shed some light on how it's supposed to wo...
Maximum packet size for a TCP connection
...
The absolute limitation on TCP packet size is 64K (65535 bytes), but in practicality this is far larger than the size of any packet you will see, because the lower layers (e.g. ethernet) have lower packet sizes.
The MTU (Maximum Transmission Unit) for Ethernet, for instance, is 15...
Static class initializer in PHP
...
Sounds like you'd be better served by a singleton rather than a bunch of static methods
class Singleton
{
/**
*
* @var Singleton
*/
private static $instance;
private function __construct()
{
// Your "heavy" initialization stuff here
}...
How to toggle a value in Python
...>> x
1
The technique generalizes to any pair of integers. The xor-by-one step is replaced with a xor-by-precomputed-constant:
>>> A = 205
>>> B = -117
>>> t = A ^ B # precomputed toggle constant
>>> x = A
>>> x ^= t # toggle
>...
Appropriate datatype for holding percent values?
... decimal is ANSI compliant, so always use that unless told otherwise (e.g. by your company's coding standards).
Example Scenarios
For your case (0.00% to 100.00%) you'd want decimal(5,4).
For the most common case (0% to 100%) you'd want decimal(3,2).
In both of the above, the check constraints w...