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What is @RenderSection in asp.net MVC
...
If you have a _Layout.cshtml view like this
<html>
<body>
@RenderBody()
@RenderSection("scripts", required: false)
</body>
</html>
then you can have an index.cshtml content view like this
...
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')...
What is the difference between varchar and varchar2 in Oracle?
...aracters with a maximum length of 4000 bytes. If the init.ora parameter max_string_size is default, the maximum length of a VARCHAR2 can be 4000 bytes. If the init.ora parameter max_string_size = extended, the maximum length of a VARCHAR2 can be 32767 bytes
The VARCHAR data type stores character st...
What is :: (double colon) in Python when subscripting sequences?
...n custom classes to make it do whatever you want
class C(object):
def __getitem__(self, k):
return k
# Single argument is passed directly.
assert C()[0] == 0
# Multiple indices generate a tuple.
assert C()[0, 1] == (0, 1)
# Slice notation generates a slice object.
assert C()[1:2:3] =...
How should a model be structured in MVC? [closed]
...a mock database dependency in your model):
class Database {
protected $_conn;
public function __construct($connection) {
$this->_conn = $connection;
}
public function ExecuteObject($sql, $data) {
// stuff
}
}
abstract class Model {
protected $_db;
public fu...
hidden symbol ... is referenced by DSO 剖析 - C/C++ - 清泛网 - 专注C/C++及内核技术
...因是符号(函数)未导出导致的，添加导出申明即可解决：__attribute__ ((visibility("default")) DSO 是动态共享对象，Linux报“hidden symbol ... is referenced by DSO”错误的原因是符号(函数)未导出导致的，添加导出申明即可解决：
__attribute__ (...
C++简练易用的线程池(threadpool)及上下文隔离的无锁线程池(isolated_threa...
...易用的线程池(threadpool)及上下文隔离的无锁线程池(isolated_threadpool)完整实现本文主要介绍两种C++线程池模型完整代码，经过实战考验的，效率已极致优化的代码，可直接用于实际项目开发。1、C++简练易用的线程池(threadpool)
完整...
JSON serialization of Google App Engine models
...nary that can be passed to simplejson:
import datetime
import time
SIMPLE_TYPES = (int, long, float, bool, dict, basestring, list)
def to_dict(model):
output = {}
for key, prop in model.properties().iteritems():
value = getattr(model, key)
if value is None or isinstance(...
GitHub pages are not updating
...
you can tell jekyll to show "future" posts by adding future: true to your _config.yml
and/or add timezone: TIMEZONE to specify your timezone.
See https://jekyllrb.com/docs/configuration/ for more info.
share
|
...
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...