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SQL how to increase or decrease one for a int column in one command
I have an Orders table which has a Quantity column. During check in or check out, we need to update that Quantity column by one. Is there a way to do this in one action or we have to get the existing value and then add or minus one on top of it?
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What do two question marks together mean in C#?
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It's the null coalescing operator, and quite like the ternary (immediate-if) operator. See also ?? Operator - MSDN.
FormsAuth = formsAuth ?? new FormsAuthenticationWrapper();
expands to:
FormsAuth = formsAuth != null ? formsAuth : new FormsAuthenticationWrapper();
which further ...
Convert a float64 to an int in Go
...t64 to an int in Go? I know the strconv package can be used to convert anything to or from a string, but not between data types where one isn't a string. I know I can use fmt.Sprintf to convert anything to a string, and then strconv it to the data type I need, but this extra conversion seems a...
Uncaught SyntaxError: Unexpected token with JSON.parse
...ed to convert a string containing JSON notation into a Javascript object.
Your code turns the object into a string (by calling .toString()) in order to try to parse it as JSON text.
The default .toString() returns "[object Object]", which is not valid JSON; hence the error.
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What is the difference between a port and a socket?
This was a question raised by one of the software engineers in my organisation. I'm interested in the broadest definition.
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What is the difference between supervised learning and unsupervised learning? [closed]
..., what is the difference between supervised and unsupervised learning?
Can you provide a basic, easy explanation with an example?
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How to save a BufferedImage as a File
I am using the imgscalr Java library to resize an image .
6 Answers
6
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How to “test” NoneType in python?
I have a method that sometimes returns a NoneType value. So how can I question a variable that is a NoneType? I need to use if method, for example
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Remove columns from dataframe where ALL values are NA
I'm having trouble with a data frame and couldn't really resolve that issue myself:
The dataframe has arbitrary properties as columns and each row represents one data set .
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How do I get list of methods in a Python class?
...ough the methods in a class, or handle class or instance objects differently based on the methods present. How do I get a list of class methods?
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