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Does MySQL index foreign key columns automatically?
... where the foreign key columns are listed as the first columns in the same order. Such an index is created on the referencing table automatically if it does not exist. (This is in contrast to some older versions, in which indexes had to be created explicitly or the creation of foreign key constraint...
Code Golf: Collatz Conjecture
...t;^v are arrows that change direction the "program counter" wanders. | and _ are conditionals that go up/down or left/right depending on whether the value on stack is true or false. The whole "code arena" wraps around through top-bottom and left-right.
– SF.
Ma...
The SMTP server requires a secure connection or the client was not authenticated. The server respons
....Credentials after calling SmtpClient.UseDefaultCredentials = false.
The order is important as setting SmtpClient.UseDefaultCredentials = false will reset SmtpClient.Credentials to null.
share
|
i...
Hash Map in Python
...anged easily.
Rehashing is out of scope of this code.
class Node:
def __init__(self, key, value):
self.key = key
self.value = value
self.next = None
class HashMap:
def __init__(self):
self.store = [None for _ in range(16)]
def get(self, key):
ind...
Finding duplicate values in MySQL
...
Very good. I added ORDER BY varchar_column DESC to the end of query.
– trante
May 28 '14 at 20:25
8
...
In Python, how do I index a list with another list?
...ng, either by integer, slice or index-list:
class Flexlist(list):
def __getitem__(self, keys):
if isinstance(keys, (int, slice)): return list.__getitem__(self, keys)
return [self[k] for k in keys]
Which, for your example, you would use as:
L = Flexlist(['a', 'b', 'c', 'd', 'e...
Casting vs using the 'as' keyword in the CLR
...bject obj) cil managed
{
// Code size 22 (0x16)
.maxstack 8
IL_0000: ldarg.1
IL_0001: isinst MyClass
IL_0006: brfalse.s IL_0015
IL_0008: ldarg.1
IL_0009: castclass MyClass
IL_000e: pop
IL_000f: ldarg.1
IL_0010: call void [mscorlib]System.Console::WriteL...
Use underscore inside Angular controllers
...d:
var underscore = angular.module('underscore', []);
underscore.factory('_', ['$window', function($window) {
return $window._; // assumes underscore has already been loaded on the page
}]);
And then you can ask for the _ in your app's module:
// Declare it as a dependency of your module
var a...
What is “android:allowBackup”?
...you to copy your persistent application data to remote "cloud" storage, in order to provide a restore point for the application data and settings. If a user performs a factory reset or converts to a new Android-powered device, the system automatically restores your backup data when the application i...
How to convert vector to array
...?
If you're calling an API function that expects the former, you can do do_something(&v[0], v.size()), where v is a vector of doubles. The elements of a vector are contiguous.
Otherwise, you just have to copy each element:
double arr[100];
std::copy(v.begin(), v.end(), arr);
Ensure not only...