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How to pull a random record using Django's ORM?
...
Using order_by('?') will kill the db server on the second day in production. A better way is something like what is described in Getting a random row from a relational database.
from django.db.models.aggregates import Count
from random...
What is the use of static variable in C#? When to use it? Why can't I declare the static variable in
...red. Let me explain this with an example:
class circle
{
public float _PI =3.14F;
public int Radius;
public funtionArea(int radius)
{
return this.radius * this._PI
}
}
class program
{
public static void main()
{
Circle c1 = new Cirle();
flo...
Win10正式版官方原版ISO镜像下载大全（64位&32位） - 软件下载 - 清泛网 - ...
...方原版 正式版【64位简体中文家庭 专业版】 文件名：cn_windows_10_multiple_editions_x64_dvd_6848463.iso 体积：4.01GB SHA1：C71D49A6...【64位简体中文家庭/专业版】
文件名：cn_windows_10_multiple_editions_x64_dvd_6848463.iso
体积：4.01GB
...
file_get_contents(“php://input”) or $HTTP_RAW_POST_DATA, which one is better to get the body of JSON
file_get_contents("php://input") or $HTTP_RAW_POST_DATA - which one is better to get the body of JSON request?
6 Answers...
How do I bind a WPF DataGrid to a variable number of columns?
...c readonly Dictionary<DataGrid, NotifyCollectionChangedEventHandler> _handlers;
static DataGridColumnsBehavior()
{
_handlers = new Dictionary<DataGrid, NotifyCollectionChangedEventHandler>();
}
private static void BindableColumnsPropertyChanged(DependencyObject ...
How to profile a bash shell script slow startup?
...
PS4='+ $EPOCHREALTIME\011 '
As pointed out by @pawamoy, you can use BASH_XTRACEFD to send the output of the trace to a separate file descriptor if you have Bash 4.1 or later. From this answer:
#!/bin/bash
exec 5> command.txt
BASH_XTRACEFD="5"
echo -n "hello "
set -x
echo -n world
set +x
e...
Difference between abstract class and interface in Python
... NotImplementedError("Class %s doesn't implement aMethod()" % (self.__class__.__name__)) is more informative error message :)
– naught101
Sep 3 '14 at 1:43
9
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SQL Server: Filter output of sp_who2
Under SQL Server, is there an easy way to filter the output of sp_who2? Say I wanted to just show rows for a certain database, for example.
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How to tell if JRE or JDK is installed
...java in system environment).
And if you haven't, add it via
export JAVA_HOME=/path/to/java/jdk1.x
and if you unsure if you have java at all on your system just use find in terminal
i.e. find / -name "java"
share
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Passing parameters to addTarget:action:forControlEvents
... creating several buttons within a for loop:
for (NSInteger i = 0; i < _phoneNumbers.count; i++) {
UIButton *phoneButton = [[UIButton alloc] initWithFrame:someFrame];
[phoneButton setTitle:_phoneNumbers[i] forState:UIControlStateNormal];
[phoneButton setTag:i];
[phoneButton ad...