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How do I run a Ruby file in a Rails environment?
...------
#!/usr/bin/env /Users/me/rails_project/script/rails runner
Product.all.each { |p| p.price *= 2 ; p.save! }
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Error 1022 - Can't write; duplicate key in table
...ou can not have the same foreign key names in the database tables.
Check all your tables and all your foreign keys and avoid having two foreign keys with the same exact name.
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How to test android referral tracking?
...ust run in a terminal:
adb shell
am broadcast -a com.android.vending.INSTALL_REFERRER -n <your.package>/.<path.up.until.your.BroadcastReceiver> --es "referrer" "utm_source=test_source\&utm_medium=test_medium\&utm_term=test_term\&utm_content=test_content\&utm_campaign=te...
Android Studio needs JDK 7 for Android-L mac
...
Setting the directory to:
/Library/Java/JavaVirtualMachines/jdk1.7.0_60.jdk/Contents/Home
in JDK settings solved my issue. I had the same problem getting started up. Hope this helps!
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Most efficient method to groupby on an array of objects
...g callback functions to return a sorting criteria
– y_nk
Jul 6 '16 at 16:50
118
Here is one that ...
How to set a Django model field's default value to a function call / callable (e.g., a date relative
... to create a field in the class.
PRE Django 1.7
Django lets you pass a callable as the default, and it will invoke it each time, just as you want:
from datetime import datetime, timedelta
class MyModel(models.Model):
# default to 1 day from now
my_date = models.DateTimeField(default=lambda: ...
Backbone.View “el” confusion
...
A views el is where all the event binding takes place. You don't have to use it but if you want backbone to fire events you need to do your rendering work on the el. A views el is a DOM element but it does not have to be a pre-existing element. ...
Manipulating an Access database from Java without ODBC
...
UCanAccess is a pure Java JDBC driver that allows us to read from and write to Access databases without using ODBC. It uses two other packages, Jackcess and HSQLDB, to perform these tasks. The following is a brief overview of how to get it set up.
Option 1: Using...
Check if a variable is of function type
...unction(functionToCheck) {
return functionToCheck && {}.toString.call(functionToCheck) === '[object Function]';
}
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How to throw std::exceptions with variable messages?
...atter & operator << (const Type & value)
{
stream_ << value;
return *this;
}
std::string str() const { return stream_.str(); }
operator std::string () const { return stream_.str(); }
enum ConvertToString
{
to_str
};...