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Rails migrations: self.up and self.down versus change
... For example, in your case what is the reverse operation of add_column to call when you rollback? Of course it's remove_column. What is the inverse of create_table? It's drop_table. So in these cases rails know how to rollback and define a down method is superfluous (you can see in the documentation...
How can I keep my fork in sync without adding a separate remote?
...:
There isn't anything to compare.
someone:master is up to date with all commits from me:master. Try switching the base for your comparison.
Click on switching the base on this page:
Then you get to see all the commits made to someone/foobar after the day you forked it.
Click on Create p...
Logging levels - Logback - rule-of-thumb to assign log levels
...y requires human intervention. The "2AM rule" applies here- if you're on call, do you want to be woken up at 2AM if this condition happens? If yes, then log it as "error".
warn: an unexpected technical or business event happened, customers may be affected, but probably no immediate human intervent...
How to hide databases that I am not allowed to access
... I connect to my Heroku - Postgresql database via pgAdmin3 , It lists all the tables (about 2600). Every time I open the pgAdmin3 I have to find my own database.
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Why are nested weights bad for performance? Alternatives?
...with non-zero weights, then the number of measurements
increase exponentially.
It's better to use RelativeLayouts and adjust your view according to the places of other views without using specific dpi values.
share
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Hidden features of Python [closed]
...ue, and then comparing True < 10, which is also True, then no, that's really not what happens (see the last example.) It's really translating into 1 < x and x < 10, and x < 10 and 10 < x * 10 and x*10 < 100, but with less typing and each term is only evaluated once.
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Is there a good reason I see VARCHAR(255) used so often (as opposed to another length)?
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Historically, 255 characters has often been the maximum length of a VARCHAR in some DBMSes, and it sometimes still winds up being the effective maximum if you want to use UTF-8 and have the column indexed (because of index length lim...
Handle spring security authentication exceptions with @ExceptionHandler
...m using Spring MVC's @ControllerAdvice and @ExceptionHandler to handle all the exception of a REST Api. It works fine for exceptions thrown by web mvc controllers but it does not work for exceptions thrown by spring security custom filters because they run before the controller methods are invok...
How do you create a remote Git branch?
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First, you create your branch locally:
git checkout -b <branch-name> # Create a new branch and check it out
The remote branch is automatically created when you push it to the remote server. So when you feel ready for it, you can just do:
git push &...
Use tab to indent in textarea
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I don't usually copy code straight from Stackoverflow and paste it into my project and have it work, but when I do, it was this code. Thanks for this.
– Flat Cat
Dec 15 '14 at 14:58
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