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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
10
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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 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 = ":...
How to fix: Handler “PageHandlerFactory-Integrated” has a bad module “ManagedPipelineHandler” in its
I am configuring an MVC 3 project to work on a local install of IIS and came across the following 500 error:
19 Answers
...
Notepad++ add to every line
...eplace with textbox
Place cursor in the first line of the file to ensure all lines are affected
Click Replace All button
To add a word, such as test, at the end of each line:
Type $ in the Find what textbox
Type test in the Replace with textbox
Place cursor in the first line of...
Check if a string has white space
... "/" characters are sufficient.
/^\s+$/ is checking whether the string is ALL whitespace:
^ matches the start of the string.
\s+ means at least 1, possibly more, spaces.
$ matches the end of the string.
Try replacing the regex with /\s/ (and no quotes)
...
Php multiple delimiters in explode
...
You can take the first string, replace all the @ with vs using str_replace, then explode on vs or vice versa.
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Xcode source automatic formatting
...ghly dependent on the automatic formatting in Visual Studio 2008. Specifically, I will use the CTRL + K , D keyboard shortcut to force things back into shape after my sloppy implementation.
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mongodb find by multiple array items
...o find documents where words contains both elements (text and here) using $all:
db.things.find({ words: { $all: ["text", "here"] }});
or either of them (text or here) using $in:
db.things.find({ words: { $in: ["text", "here"] }});
...