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Reference — What does this symbol mean in PHP?
... have the same results.
Pre-increment is a little bit faster because it really increments the variable and after that 'returns' the result. Post-increment creates a special variable, copies there the value of the first variable and only after the first variable is used, replaces its value with seco...
Unique BooleanField value in Django?
... save method of the model and if you've set the boolean to True, make sure all others are set to False.
from django.db import transaction
class Character(models.Model):
name = models.CharField(max_length=255)
is_the_chosen_one = models.BooleanField()
def save(self, *args, **kwargs):
...
enum - getting value of enum on string conversion
...>> member.value
1
You could add a __str__ method to your enum, if all you wanted was to provide a custom string representation:
class D(Enum):
def __str__(self):
return str(self.value)
x = 1
y = 2
Demo:
>>> from enum import Enum
>>> class D(Enum):
...
Nested or Inner Class in PHP
...There are several compelling reasons for using them:
It is a way of logically grouping classes that are only used in one place.
If a class is useful to only one other class, then it is logical to
relate and embed it in that class and keep the two together.
It increases encapsulation.
...
What is the difference between “px”, “dip”, “dp” and “sp”?
...lems with dp while everything works fine with dip
– DallaRosa
Jul 4 '11 at 6:07
255
One note abou...
How to [recursively] Zip a directory in PHP?
...ce), file_get_contents($source));
}
return $zip->close();
}
Call it like this:
Zip('/folder/to/compress/', './compressed.zip');
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What is the best collation to use for MySQL with PHP? [closed]
...site where you aren't 100% sure of what will be entered? I understand that all the encodings should be the same, such as MySQL, Apache, the HTML and anything inside PHP.
...
SQL Server: Query fast, but slow from procedure
... the quoted answer did not solve the problem for me. The query still ran really slow from a stored procedure.
I found another answer here "Parameter Sniffing", Thanks Omnibuzz. Boils down to using "local Variables" in your stored procedure queries, but read the original for more understanding, it...
ADB No Devices Found
I am attempting to install an Android app on my brand new Nexus 10 . I have a .apk file. I have downloaded the Android SDK, installed "Android SDK Tools", "Android SDK Platform-tools", and Google USB Driver. I have checked the setting on my Nexus 10 for "Unknown Sources".
...
How to drop all tables in a SQL Server database?
...y tables.
I found that code that works and does everything you try (delete all tables from your database):
DECLARE @Sql NVARCHAR(500) DECLARE @Cursor CURSOR
SET @Cursor = CURSOR FAST_FORWARD FOR
SELECT DISTINCT sql = 'ALTER TABLE [' + tc2.TABLE_SCHEMA + '].[' + tc2.TABLE_NAME + '] DROP [' + rc1.C...