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Is there a version control system for database structure changes?
...keeps track of your current db version.
To migrate up, you run a command called "db:migrate" which looks at your version and applies the needed scripts. You can migrate down in a similar way.
The migration scripts themselves are kept in a version control system -- whenever you change the database ...
Aligning a float:left div to center?
I want to have a group of images display horizontally across the page. Each image has a few link below it so I need to put a container around each image/link-group.
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looping through an NSMutableDictionary
How do I loop through all objects in a NSMutableDictionary regardless of the keys?
6 Answers
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Force R to stop plotting abbreviated axis labels - e.g. 1e+00 in ggplot2
... being abbreviated - e.g. 1e+00, 1e+01 along the x axis once plotted? Ideally, I want to force R to display the actual values which in this case would be 1,10 .
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How does one use rescue in Ruby without the begin and end block
... Inline rescue is not a good practice as it rescues StandardError and all its subclasses, like NameError – meaning that even a typo in your code won't raise an error.. See thoughtbot.com/blog/don-t-inline-rescue-in-ruby.
– BrunoFacca
Sep 19 '19 at 18:25
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Access to Modified Closure
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In this case, it's okay, since you are actually executing the delegate within the loop.
If you were saving the delegate and using it later, however, you'd find that all of the delegates would throw exceptions when trying to access files[i] - they're capturing the var...
What is the `sensor` parameter for in the Google Places API?
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Really? Could you please provide some link, where this is written. I have not found this anywhere. (Also wondering why the price is different and what is cheaper:)
– TN.
Dec 25 '11 at 21:1...
unix domain socket VS named pipes?
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UNIX-domain sockets are generally more flexible than named pipes. Some of their advantages are:
You can use them for more than two processes communicating (eg. a server process with potentially multiple client processes connecting);
They are bidirecti...
What happens when a duplicate key is put into a HashMap?
...laces the previous value associated with the given key in the map (conceptually like an array indexing operation for primitive types).
The map simply drops its reference to the value. If nothing else holds a reference to the object, that object becomes eligible for garbage collection. Additionall...
How to copy a file to a remote server in Python using SCP or SSH?
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You can call the scp bash command (it copies files over SSH) with subprocess.run:
import subprocess
subprocess.run(["scp", FILE, "USER@SERVER:PATH"])
#e.g. subprocess.run(["scp", "foo.bar", "joe@srvr.net:/path/to/foo.bar"])
If you'...