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What is the difference between char, nchar, varchar, and nvarchar in SQL Server?
...on as illustrated below.
DECLARE @T TABLE
(
C1 VARCHAR(20) COLLATE Chinese_Traditional_Stroke_Order_100_CS_AS_KS_WS,
C2 NVARCHAR(20)COLLATE Chinese_Traditional_Stroke_Order_100_CS_AS_KS_WS
)
INSERT INTO @T
VALUES (N'中华人民共和国',N'中华人民共和国'),
(N'abc',N'abc')...
Get names of all keys in the collection
...You could do this with MapReduce:
mr = db.runCommand({
"mapreduce" : "my_collection",
"map" : function() {
for (var key in this) { emit(key, null); }
},
"reduce" : function(key, stuff) { return null; },
"out": "my_collection" + "_keys"
})
Then run distinct on the resulting collecti...
When should use Readonly and Get only properties
...during the construction of an object (in the constructor).
private string _name = "Foo"; // field for property Name;
private bool _enabled = false; // field for property Enabled;
public string Name{ // This is a readonly property.
get {
return _name;
}
}
public bool Enabled{ // This is ...
Fatal error: “No Target Architecture” in Visual Studio
...
_WIN32 identifier is not defined.
use #include <SDKDDKVer.h>
MSVS generated projects wrap this include by generating a local "targetver.h"which is included by "stdafx.h" that is comiled into a precompiled-header throu...
How do I install cURL on cygwin?
...
How to install the lynx .
– qg_java_17137
Aug 21 '18 at 7:11
Not working for me. It did some pr...
Why does HTML5 form-validation allow emails without a dot?
...ss (eg localhost is a valid domain). See http://en.wikipedia.org/wiki/Email_address#Examples
Also, keep in mind that you should always do the input validation in server. The client side validation should be only for giving feedback to the user and not be relied on, since it can be easily bypassed.
...
How to detect the end of loading of UITableView
...
Swift 3 & 4 & 5 version:
func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {
if let lastVisibleIndexPath = tableView.indexPathsForVisibleRows?.last {
if indexPath == lastVisibleIndexPath {
...
Django Model - Case-insensitive Query / Filtering
...
I solved it like this:
MyClass.objects.filter(name__iexact=my_parameter)
There is even a way to use it for substring search:
MyClass.objects.filter(name__icontains=my_parameter)
There's a link to the documentation.
...
What is the copy-and-swap idiom?
...nclude <algorithm> // std::copy
#include <cstddef> // std::size_t
class dumb_array
{
public:
// (default) constructor
dumb_array(std::size_t size = 0)
: mSize(size),
mArray(mSize ? new int[mSize]() : nullptr)
{
}
// copy-constructor
dumb_array(...
Unique fields that allow nulls in Django
...pty string by providing your own customized model form for Foo with a clean_bar method that turns the empty string into None:
class FooForm(forms.ModelForm):
class Meta:
model = Foo
def clean_bar(self):
return self.cleaned_data['bar'] or None
class FooAdmin(admin.ModelAdmin...