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What is scope/named_scope in rails?
...stead of always writing this you could, however, do something like this.
#File: users.rb
class User < ActiveRecord::Base
scope :newsletter, where(subscribed_to_newsletter: true)
#yada yada
end
If you're using Rails 4 or newer, do this instead:
#File: users.rb
class User < ActiveRecord:...
What exactly do the Vagrant commands do?
...y is being used is useful. You could do use normal ssh command - ssh -i keyfile ..
vagrant status <vmname>
This command is a wrapper which provides the information on the status of vm. It could be running, saved and powered off.
vagrant reload
If you make any changes to the configuration in ...
ERROR: Error 1005: Can't create table (errno: 121)
...ata directory in command line:
find . -iname '#*'
After discovering the filename, such as #sql-9ad_15.frm, I was able to drop that orphaned table in MySQL:
USE myschema;
DROP TABLE `#mysql50##sql-9ad_15`;
After doing so, I was then able to successfully run my ALTER TABLE.
For completeness, as...
What's the difference between ngModel.$modelValue and ngModel.$viewValue
...ive or an Object in your custom controls. A good example, is the <input file="type"> component, where viewValue contains FileList object with files attached by the user. The Angular docs are confusing about this right now and should be updated.
– demisx
F...
How do I check for a network connection?
... on www.msftncsi.com, then requests http://www.msftncsi.com/ncsi.txt. This file is a plain-text file and contains only the text 'Microsoft NCSI'.
NCSI sends a DNS lookup request for dns.msftncsi.com. This DNS address should resolve to 131.107.255.255. If the address does not match, then it is assume...
Renaming table in rails
..., running rake db:migrate or rake db:rollback will not rename the model.rb file. You will need to manually change the model.rb file.
– 9monkeys
Jun 8 '12 at 14:00
...
Is cout synchronized/thread-safe?
...al.intro.using.concurrency.io
the key stuff is probably:
The __basic_file type is simply a
collection of small wrappers around
the C stdio layer (again, see the link
under Structure). We do no locking
ourselves, but simply pass through to
calls to fopen, fwrite, and so forth.
So...
How to check if APK is signed or “debug build”?
...
First add this to your build.gradle file, this will also allow side by side running of debug and release builds:
buildTypes {
debug {
applicationIdSuffix ".debug"
}
}
Add this method:
public static boolean isDebug(Context context) {
Stri...
Difference between “change” and “input” event for an `input` element
...
When element is :checked, either by keyboard or mouse click
"date" and "file":
When a change is explicitly committed, ie. selecting a date or file
"text":
When the element loses focus after its value has been changed, but not committed
Fair warning that browsers are fickle, and don't alway...
How do you import classes in JSP?
...
Why would you need to import File and IOException classes OR is it that you were just informing the questioner about how to import more than one class in the JSP?
– Vijay Dev
Oct 27 '08 at 8:10
...