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Testing Abstract Classes
...oncrete methods, and this concrete methods can be tested.
It is not so uncommon, when writing some library code, to have certain base class that you expect to extend in your application layer. And if you want to make sure that library code is tested, you need means to UT the concrete methods of ab...
Rails: Default sort order for a rails model?
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community wiki
23 revs, 4 users 82%Michael Durrant
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How to add a footer to a UITableView in Storyboard
...than 0 prototype cells specified. Otherwise, the dragged-in view always becomes the header. To fix this, change the number of prototype cells to 1, drag in the view underneath the one prototype cell, then change the number of prototype cells back to 0.
– John Brewer
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What is the difference between pluck and collect in Rails?
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COUNT DISTINCT with CONDITIONS
...me;
The first count(distinct...) is easy.
The second one, looks somewhat complex, is actually the same as the first one, except that you use case...when clause. In the case...when clause, you filter only positive values. Zeros or negative values would be evaluated as null and won't be included in ...
Rails :dependent => :destroy VS :dependent => :delete_all
...rectly in your application and deletes by SQL :
DELETE * FROM users where compagny_id = XXXX
With the :destroy, there is an instantiation of all of your children. So, if you can't destroy it or if each has their own :dependent, its callbacks can be called.
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Send email using java
...SMTP server. You need to supply your Google username and password.
import com.sun.mail.smtp.SMTPTransport;
import java.security.Security;
import java.util.Date;
import java.util.Properties;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.Session;
import javax.mail...
How do I change the formatting of numbers on an axis with ggplot?
...erplot of some data, all is fine except that the numbers on the y-axis are coming out with computer style exponent formatting, i.e. 4e+05, 5e+05, etc. This is obviously unacceptable, so I want to get it to display them as 500,000, 400,000, and so on. Getting a proper exponent notation would also be ...
How can I edit a view using phpMyAdmin 3.2.4?
I need to simply edit a very complicated view in phpMyAdmin 3.2.4 but I cannot figure how to do that. Any suggestions?
Thanks!
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WebException how to get whole response with a body?
...this case it's obvious to the attention-paying reader and @iwtu, but Fully comprehensive answers can make the real difference to the beginners reading this answer;)
– Jeroen
Nov 18 '16 at 12:18
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