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SQL Add foreign key to existing column
...rst and then re-run the statement.
ALTER TABLE Employees
ADD CONSTRAINT FK_ActiveDirectories_UserID FOREIGN KEY (UserID)
REFERENCES ActiveDirectories(id);
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Regex to Match Symbols: !$%^&*()_+|~-=`{}[]:";'?,./
...l character in character classes, so it needs to be first:
/[-!$%^&*()_+|~=`{}\[\]:";'<>?,.\/]/
You also need to escape the other regular expression metacharacters.
Edit:
The hyphen is special because it can be used to represent a range of characters. This same character class can be ...
Finding the index of an item in a list
...atch, you can give index a hint. For instance, in this snippet, l.index(999_999, 999_990, 1_000_000) is roughly five orders of magnitude faster than straight l.index(999_999), because the former only has to search 10 entries, while the latter searches a million:
>>> import timeit
>>&g...
How can I uninstall an application using PowerShell?
...
$app = Get-WmiObject -Class Win32_Product | Where-Object {
$_.Name -match "Software Name"
}
$app.Uninstall()
Edit: Rob found another way to do it with the Filter parameter:
$app = Get-WmiObject -Class Win32_Product `
-Filter "N...
Create singleton using GCD's dispatch_once in Objective-C
...er here: instancetype
+ (instancetype)sharedInstance
{
static dispatch_once_t once;
static id sharedInstance;
dispatch_once(&once, ^
{
sharedInstance = [self new];
});
return sharedInstance;
}
+ (Class*)sharedInstance
{
static dispatch_once_t once;
...
How to get the error message from the error code returned by GetLastError()?
...rror message has been recorded
LPSTR messageBuffer = nullptr;
size_t size = FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
NULL, errorMessageID, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPSTR)&a...
How do you round a floating point number in Perl?
...foreach my $i ( 0.5, 1.5, 2.5, 3.5 ) {
printf "$i -> %.0f\n", $i;
}
__END__
0.5 -> 0
1.5 -> 2
2.5 -> 2
3.5 -> 4
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UIButton Image + Text IOS
...
I think you are looking for this solution for your problem:
UIButton *_button = [UIButton buttonWithType:UIButtonTypeCustom];
[_button setFrame:CGRectMake(0.f, 0.f, 128.f, 128.f)]; // SET the values for your wishes
[_button setCenter:CGPointMake(128.f, 128.f)]; // SET the values for your wishes...
How to check if a variable is a dictionary in Python?
...t, defaultdict, or Counter from the collections module:
if isinstance(any_object, dict):
But there are even more flexible options.
Supporting abstractions:
from collections.abc import Mapping
if isinstance(any_object, Mapping):
This allows the user of your code to use their own custom implem...
JavaScript: What are .extend and .prototype used for?
...(){
var initializing = false, fnTest = /xyz/.test(function(){xyz;}) ? /\b_super\b/ : /.*/;
// The base Class implementation (does nothing)
this.Class = function(){};
// Create a new Class that inherits from this class
Class.extend = function(prop) {
var _super = this.prototype;
...