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What exactly is Arel in Rails 3.0?
I understand that it is a replacement for ActiveRecord and that it uses objects instead of queries.
4 Answers
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Value of i for (i == -i && i != 0) to return true in Java
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The only int value for which it works is Integer.MIN_VALUE.
It's because integers are negated using the two's complement way.
Using
System.out.println(Integer.toBinaryString(Integer.MIN_VALUE));
you see that Integer.MIN_VALUE is
100000000...
Split files using tar, gz, zip, or bzip2 [closed]
... file when (de)compressing. Use the tar -C option to use a different directory for the resulting files. btw if the archive consists from only a single file, tar could be avoided and only gzip used:
# create archives
$ gzip -c my_large_file | split -b 1024MiB - myfile_split.gz_
# uncompress
$ cat my...
WWW or not WWW, what to choose as primary site name? [closed]
...matter which you choose but you should pick one and be consistent. It is more a matter of style but it is important to note that search engines consider these two URLs to be different sites:
http://www.example.com
http://example.com
So whichever you choose for aesthetic reasons should be co...
What's the difference between an exclusive lock and a shared lock?
According to wikipedia,
4 Answers
4
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Best practice for storing and protecting private API keys in applications [closed]
...ty libraries into their apps. If it's to access a service, such as Dropbox or YouTube, or for logging crashes. The number of third party libraries and services is staggering. Most of those libraries and services are integrated by somehow authenticating with the service, most of the time, this happen...
How to exit pdb and allow program to continue?
...it without the script attempting to complete. continue doesn't seems to work. How can I exit pdb and continue with my program?
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Does a finally block run even if you throw a new Exception?
..... except when:
The thread running the try-catch-finally block is killed or interrupted
You use System.exit(0);
The underlying VM is destroyed in some other way
The underlying hardware is unusable in some way
Additionally, if a method in your finally block throws an uncaught exception, then not...
Convert datetime to Unix timestamp and convert it back in python
...s, which explain about timezones and "naive" and "aware" objects.
If your original naive datetime was UTC, the way to recover it is to use utcfromtimestamp instead of fromtimestamp.
On the other hand, if your original naive datetime was local, you shouldn't have subtracted a UTC timestamp from it ...
What is a good choice of database for a small .NET application? [closed]
...ep... still getting upvotes :-/
17/03/2014 I'm still receiving upvotes for this, be mindful of the date this was originally answered. Though the main three items listed are still entirely viable, the list will tend towards becoming stale. There are further database technologies available that are...