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SQL query to find record with ID not in another table
I have two tables with binding primary key in database and I desire to find a disjoint set between them. For example,
6 Ans...
Should you declare methods using overloads or optional parameters in C# 4.0?
I was watching Anders' talk about C# 4.0 and sneak preview of C# 5.0 , and it got me thinking about when optional parameters are available in C# what is going to be the recommended way to declare methods that do not need all parameters specified?
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Select row with most recent date per user
I have a table ("lms_attendance") of users' check-in and out times that looks like this:
11 Answers
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What is the equivalent of MATLAB's repmat in NumPy
I would like to execute the equivalent of the following MATLAB code using NumPy: repmat([1; 1], [1 1 1]) . How would I accomplish this?
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NULL values inside NOT IN clause
...one using a not in where constraint and the other a left join . The table in the not in constraint had one null value (bad data) which caused that query to return a count of 0 records. I sort of understand why but I could use some help fully grasping the concept.
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What is an idiomatic way of representing enums in Go?
I'm trying to represent a simplified chromosome, which consists of N bases, each of which can only be one of {A, C, T, G} .
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SQLAlchemy: What's the difference between flush() and commit()?
What the difference is between flush() and commit() in SQLAlchemy?
5 Answers
5
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A Regex that will never be matched by anything
This might sound like a stupid question, but I had a long talk with some of my fellow developers and it sounded like a fun thing to think of.
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Choosing between qplot() and ggplot() in ggplot2 [closed]
...plot2 package for plotting in R, and one of the first things I ask myself before each plot is "well, will I use qplot or ggplot ?"
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C++ templates Turing-complete?
... note that most compilers have a limit on the depth of the recursion available.
std::cout << Factorial<4>::val << "\n";
}
That was a little fun but not very practical.
To answer the second part of the question:
Is this fact useful in practice?
Short Answer: Sort of.
Long A...