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Rails :include vs. :joins
... what I understood (with examples :))
Consider this scenario:
A User has_many comments and a comment belongs_to a User.
The User model has the following attributes: Name(string), Age(integer). The Comment model has the following attributes:Content, user_id. For a comment a user_id can be null.
...
Mongoose subdocuments vs nested schema
...g to the docs, it's exactly the same.
However, using a Schema would add an _id field as well (as long as you don't have that disabled), and presumably uses some more resources for tracking subdocs.
Alternate declaration syntax
New in v3 If you don't need access to the sub-document schema instance,...
Curly braces in string in PHP
...eral {$. Some examples to make it clear:
<?php
// Show all errors
error_reporting(E_ALL);
$great = 'fantastic';
// Won't work, outputs: This is { fantastic}
echo "This is { $great}";
// Works, outputs: This is fantastic
echo "This is {$great}";
echo "This is ${great}";
// Works
echo "This sq...
How to hide UINavigationBar 1px bottom line
..., a custom background image must
also be set with the setBackgroundImage(_:for:) method. If the default
background image is used, then the default shadow image will be used
regardless of the value of this property.
So:
let navigationBar = navigationController!.navigationBar
navigationBar.se...
In Vim is there a way to delete without putting text in the register?
... without saving it in a register, you can use the "black hole register":
"_d
Of course you could also use any of the other registers that don't hold anything you are interested in.
share
|
improv...
Determine whether an array contains a value [duplicate]
... the most efficient method of accomplishing a utility function like this.
_.includes([1, 2, 3], 3); // returns true
If you're concerned about the bulk that's being added to your application by including the whole library, know that you can include functionality separately:
var includes = require...
Why is GHC so large/big?
...njdk/jdk7) vs GHC 7 source bundle, which is 23 MB (haskell.org/ghc/download_ghc_7_0_1). GHC is not big here. Runtime size: openjdk-6-jre-headless on Ubuntu is 77 MB uncompressed vs Haskell helloworld, statically linked with its runtime, which is <1 MB. GHC is not big here.
Where GHC is big, is t...
Caching a jquery ajax response in javascript/browser
...
* @type {number}
*/
timeout: 30000,
/**
* @type {{_: number, data: {}}}
**/
data: {},
remove: function (url) {
delete localCache.data[url];
},
exist: function (url) {
return !!localCache.data[url] && ((new Date().getTime() - local...
NoClassDefFoundError: android.support.v7.internal.view.menu.MenuBuilder
... those conditions and change the app flow:
public static boolean isSamsung_4_2_2() {
String deviceMan = Build.MANUFACTURER;
String deviceRel = Build.VERSION.RELEASE;
return "samsung".equalsIgnoreCase(deviceMan) && deviceRel.startsWith("4.2.2");
}
Then in the activity's onCreat...
Django. Override save for model
...
Some thoughts:
class Model(model.Model):
_image=models.ImageField(upload_to='folder')
thumb=models.ImageField(upload_to='folder')
description=models.CharField()
def set_image(self, val):
self._image = val
self._image_changed = True
...