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'IF' in 'SELECT' statement - choose output value based on column values
...tp://dev.mysql.com/doc/refman/5.0/en/control-flow-functions.html.
Additionally, you could handle when the condition is null. In the case of a null amount:
SELECT id,
IF(type = 'P', IFNULL(amount,0), IFNULL(amount,0) * -1) as amount
FROM report
The part IFNULL(amount,0) means when amount ...
How to parse JSON data with jQuery / JavaScript?
I have a AJAX call that returns some JSON like this:
10 Answers
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How to unload a package without restarting R
...nt version and a stable version in different libraries). To guarantee that all copies are detached, use this function.
detach_package <- function(pkg, character.only = FALSE)
{
if(!character.only)
{
pkg <- deparse(substitute(pkg))
}
search_item <- paste("package", pkg, sep = ":...
Java LinkedHashMap get first or last entry
... entry is possible, but will entail iterating over the whole entry set by calling .next() until you reach the last. while (iterator.hasNext()) { lastElement = iterator.next() }
edit: However, if you're willing to go beyond the JavaSE API, Apache Commons Collections has its own LinkedMap implementa...
How to find files that match a wildcard string in Java?
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How to develop and test an app that sends emails (without filling someone's mailbox with test data)?
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LINQ .Any VS .Exists - What's the difference?
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I later made a post in another thread where I listed all the Linq "equivalents" of the .NET 2 List<> instance methods.
– Jeppe Stig Nielsen
Dec 1 '15 at 8:44
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Checking if sys.argv[x] is defined
...he end, the difference between try, except and testing len(sys.argv) isn't all that significant. They're both a bit hackish compared to argparse.
This occurs to me, though -- as a sort of low-budget argparse:
arg_names = ['command', 'x', 'y', 'operation', 'option']
args = dict(zip(arg_names, sys.a...
Download a file with Android, and showing the progress in a ProgressDialog
...Use AsyncTask and show the download progress in a dialog
This method will allow you to execute some background processes and update the UI at the same time (in this case, we'll update a progress bar).
Imports:
import android.os.PowerManager;
import java.io.InputStream;
import java.io.OutputStream...
Growing Amazon EBS Volume sizes [closed]
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All great recommendations, and I thought I'd add this article I found, which relates to expanding a Windows Amazon EC2 EBS instance using the Amazon Web UI tools to perform the necessary changes. If you're not comfortable usi...