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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 ...
HTTP Error 404.3 - Not Found" while browsing wcf service on Windows Server 2008(64bit)
...trol panel -> Turn Windows feature on or off -> and make sure you've all the options ticked as mentioned in below screenshot.
You might need to activate each box and accept in case you get errors when activating all features at once
...
What is “vectorization”?
...vec" instructions, and even some ARM chips have a vector instruction set, called NEON.
"Vectorization" (simplified) is the process of rewriting a loop so that instead of processing a single element of an array N times, it processes (say) 4 elements of the array simultaneously N/4 times.
(I chose 4...
Passing two command parameters using a WPF binding
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Firstly, if you're doing MVVM you would typically have this information available to your VM via separate properties bound from the view. That saves you having to pass any parameters at all to your commands.
However, you could also multi-bind and use a converter to cre...
How to quit a java app from within the program
...ention, a nonzero status code indicates abnormal termination.
This method calls the exit method in class Runtime. This method never returns normally.
The call System.exit(n) is effectively equivalent to the call:
Runtime.getRuntime().exit(n)
...
MySQL - Make an existing Field Unique
...e you don't have duplicates first, no?
– William T. Mallard
Apr 16 '14 at 20:04
1
Be sure to make...
Mapping composite keys using EF code first
...his helps.
EDIT: I just found a blog post from Julie Lerman with links to all kinds of EF 6 goodness. You can find whatever you need here.
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“implements Runnable” vs “extends Thread” in Java
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Yes: implements Runnable is the preferred way to do it, IMO. You're not really specialising the thread's behaviour. You're just giving it something to run. That means composition is the philosophically "purer" way to go.
In practical terms, it means you can implement Runnable and extend from anot...
Why would you use String.Equals over ==? [duplicate]
I recently was introduced to a large codebase and noticed all string comparisons are done using String.Equals() instead of ==
...
How can I ensure that a division of integers is always rounded up?
...ive when the two operands have opposite signs
If the left operand is the smallest representable int and the right operand is –1, an overflow occurs. [...] it is implementation-defined as to whether [an ArithmeticException] is thrown or the overflow goes unreported with the resulting value being th...