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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...
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 ...
How to find unused/dead code in java projects [closed]
...n large java projects? Our product has been in development for some years, and it is getting very hard to manually detect code that is no longer in use. We do however try to delete as much unused code as possible.
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How do I debug error ECONNRESET in Node.js?
I'm running an Express.js application using Socket.io for a chat webapp
and I get the following error randomly around 5 times during 24h.
The node process is wrapped in forever and it restarts itself immediately.
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