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Builder Pattern in Effective Java
I have recently started to read Effective Java by Joshua Bloch. I found the idea of the Builder pattern [Item 2 in the book] really interesting. I tried to implement it in my project but there were compilation errors. Following is in essence what I was trying to do:
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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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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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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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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...
Why are Objective-C delegates usually given the property assign instead of retain?
I'm surfing through the wonderful blog maintained by Scott Stevenson, and I'm trying to understand a fundamental Objective-C concept of assigning delegates the 'assign' property vs 'retain'. Note, the both are the same in a garbage collected environment. I'm mostly concerned with a non-GC based envi...