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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...
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...
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
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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...
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...
How to re-create database for Entity Framework?
...lete.
2 )Go to Solution Explorer, click show All Files icon.
3) Go to App_Data, right click and delete all ".mdf" files for this project.
4) Delete Migrations folder by right click and delete.
5) Go to SQL Server Management Studio, make sure the DB for this project is not there, otherwise delete...
What is Scala's yield?
...I use yield instead of map? This map code is equivalent val res = args.map(_.toUpperCase) , right?
– Geo
Jun 27 '09 at 12:23
4
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How can I maximize a split window?
...l T) to move any open window to its own tab.
As mentioned by others Ctrl+W_ / Ctrl+W| to maximize within the current tab/window layout (while respecting min height/width settings for various other windows).
(Ctrl+W= resizes all windows to equal size, respecting the minimum height/width settings)
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