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How to create an object for a Django model with a many to many field?
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For future visitors, you can create an object and all of its m2m objects in 2 queries using the new bulk_create in django 1.4. Note that this is only usable if you don't require any pre or post-processing on the data with save() methods or signals. What you insert is exactly...
Permanently add a directory to PYTHONPATH?
...n environment variable in your chosen platform and shell, since it's not really a programming question per se.
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Auto layout constraints issue on iOS7 in UITableViewCell
...n the cell is reused like this:
For Static UITableViewController:
#ifdef __IPHONE_OS_VERSION_MIN_REQUIRED
#if __IPHONE_OS_VERSION_MIN_REQUIRED < __IPHONE_8_0
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell = [sup...
Functional programming - is immutability expensive? [closed]
...’d like to clarify some points.
The “in-place” quicksort isn’t really in-place (and quicksort is not by definition in-place). It requires additional storage in the form of stack space for the recursive step, which is in the order of O(log n) in the best case, but O(n) in the worst case.
Im...
What is function overloading and overriding in php?
...that method.
In PHP, you can only overload methods using the magic method __call.
An example of overriding:
<?php
class Foo {
function myFoo() {
return "Foo";
}
}
class Bar extends Foo {
function myFoo() {
return "Bar";
}
}
$foo = new Foo;
$bar = new Bar;
echo($foo-&...
Backup/Restore a dockerized PostgreSQL database
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Backup your databases
docker exec -t your-db-container pg_dumpall -c -U postgres > dump_`date +%d-%m-%Y"_"%H_%M_%S`.sql
Restore your databases
cat your_dump.sql | docker exec -i your-db-container psql -U postgres
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How to validate inputs dynamically created using ng-repeat, ng-show (angular)
... of today, it is not possible (without using a custom directive) to dynamically generate a name of an input. Indeed, checking input docs we can see that the name attribute accepts a string only.
To solve the 'dynamic name' problem you need to create an inner form (see ng-form):
<div ng-repeat="...
How to find all serial devices (ttyS, ttyUSB, ..) on Linux without opening them?
What is the proper way to get a list of all available serial ports/devices on a Linux system?
12 Answers
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How to determine if one array contains all elements of another array
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Perhaps this is easier to read:
a2.all? { |e| a1.include?(e) }
You can also use array intersection:
(a1 & a2).size == a1.size
Note that size is used here just for speed, you can also do (slower):
(a1 & a2) == a1
But I guess the first is more re...
Where to define custom error types in Ruby and/or Rails?
... error types in a Ruby library (gem) or Ruby on Rails application? Specifically:
5 Answers
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