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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
...erally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
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Difference between object and class in Scala
I'm just going over some Scala tutorials on the Internet and have noticed in some examples an object is declared at the start of the example.
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What's is the difference between train, validation and test set, in neural networks?
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The training and validation sets are used during training.
for each epoch
for each training data instance
propagate error through the network
adjust the weights
calculate the accuracy over training data
fo...
Using Emacs as an IDE
...o two, the bottom being a shell which I use to type in compile or make commands, and the top is often some sort of documentation or README file that I want to consult while I am working. Now I know there are some pretty expert Emacs users out there, and I am curious what other Emacs functionally is...
Change key pair for ec2 instance
...e it in the same subnet, otherwise you will have to terminate the instance and create it again. - see here
Attach volume A to the new micro instance, as /dev/xvdf (or /dev/sdf)
SSH to the new micro instance and mount volume A to /mnt/tmp
$ sudo mount /dev/xvdf1 /mnt/tmp
Copy ~/.ssh/authorized_keys ...
Should I use single or double colon notation for pseudo-elements?
Since IE7 and IE8 don't support the double-colon notation for pseudo-elements (e.g. ::after or ::first-letter ), and since modern browsers support the single-colon notation (e.g. :after ) for backwards compatibility, should I use solely the single-colon notation and when IE8's market share drops...
Default constructor vs. inline field initialization
What's the difference between a default constructor and just initializing an object's fields directly?
5 Answers
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Setup a Git server with msysgit on Windows [closed]
My friends and I are trying to setup Git for Windows using the tutorial Git Server: Gitosis and Cygwin on Windows , but we just keep running into problems.
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Naming of ID columns in database tables
... id you are making reporting that much more difficult. It obscures meaning and makes complex queries harder to read as well as requiring you to use aliases to differentiate on the report itself.
Further if someone is foolish enough to use a natural join in a database where they are available, you ...
Why do you program in assembly? [closed]
...ny modern 3-D Games have their high performance core engine written in C++ and Assembly.
Games (and most programs these days) aren't "written in assembly" the same way they're "written in C++". That blog isn't saying that a significant fraction of the game is designed in assembly, or that a team ...