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How to avoid the “divide by zero” error in SQL?
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@Anderson That's not true at all. Are you sure you didn't accidentally use IsNull instead of NullIf? Try it yourself! SELECT Value,1/NullIf(Value,0)FROM(VALUES(0),(5.0),(NULL))x(Value); Unless by "breaks" you mean returns a NULL? You can convert that to ...
Fastest way to check if a string is JSON in PHP?
I need a really, really fast method of checking if a string is JSON or not. I feel like this is not the best way:
30 Answer...
Set value to null in WPF binding
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I am using .NET 3.5 SP1 so it's very simple:
<TextBox Text="{Binding Price, TargetNullValue=''}"/>
Which stands for (thanks Gregor for your comment):
<TextBox Text="{Binding Price, TargetNullValue={x:Static sys:String.Empty}}"/>
sys is the imported xml namesp...
C++ STL Vectors: Get iterator from index?
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Generally, you can use the same arithmetic with STL iterators than with pointers. They are designed to be exchangeable when using STL algorithms.
– Vincent Robert
Mar 22 '09 at 21:07
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Android phone orientation overview including compass
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Roll is a function of gravity, a 90 degree roll puts all of gravity into the x register.
Pitch is the same, a 90 degree pitch up puts all of the component of gravity into the y register.
Yaw / Heading / azimuth has no effect on gravity, it is ALWAYS at right angles to gravity...
Difference between '..' (double-dot) and '…' (triple-dot) in range generation?
..... run from the beginning to the end inclusively. Those created using ... exclude the end value.
So a..b is like a <= x <= b, whereas a...b is like a <= x < b.
Note that, while to_a on a Range of integers gives a collection of integers, a Range is not a set of values, but simply a p...
Android: Difference between Parcelable and Serializable?
...ing data , parcelable objects on the other hand should not be persisted at all . It's a really bad practice
– TheAnimatrix
Mar 25 '17 at 11:16
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RegEx to make sure that the string contains at least one lower case char, upper case char, digit and
...'t know how to rephrase it in order to make it easier to understand. Especially in these small comment-boxes. I recommend you read this: regular-expressions.info/lookaround.html and if you still have question, simply post a question of your own. Good luck!
– Bart Kiers
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How to get std::vector pointer to the raw data?
...he iterator returned by begin() (as the compiler warns, this is not technically allowed because something.begin() is an rvalue expression, so its address cannot be taken).
Assuming the container has at least one element in it, you need to get the address of the initial element of the container, whi...
Get hostname of current request in node.js Express
...y have several Network Cards and unless you specify it node will listen on all of them, so you don't know on which NIC the request came in, before it comes in.
Hostname is a DNS matter --
Don't forget that several DNS aliases can point to the same machine.
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