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What is eager loading?
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There are three levels:
Eager loading: you do everything when asked. Classic example is when you multiply two matrices. You do all the calculations. That's eager loading;
Lazy loading: you only do a calculation when required. In the previous example, you don't do any ...
Is it wrong to use Deprecated methods or classes in Java?
...ases be removed. That is, no, it's not wrong, but there is a better way of doing it, which is more robust against API changes.
2. What if I don't change any method and run my application with warnings that I have, will it create any performance issue.
Most likely no. It will continue to work a...
Can I use Class.newInstance() with constructor arguments?
I would like to use Class.newInstance() but the class I am instantiating does not have a nullary constructor. Therefore I need to be able to pass in constructor arguments. Is there a way to do this?
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Eclipse error: “The import XXX cannot be resolved”
...work with Hibernate in Eclipse.
I'm creating a new simple project and I've downloaded a collegue project too, via CVS.
Both don't work, while on my collegue's Eclipse do.
The problem is that, for each import of an Hibernate class, Eclipse says:
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MySQL: determine which database is selected?
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Just use mysql_query (or mysqli_query, even better, or use PDO, best of all) with:
SELECT DATABASE() FROM DUAL;
Addendum:
There is much discussion over whether or not FROM DUAL should be included in this or not. On a technical level, it is a holdover from Oracle and can safely ...
Java HTTPS client certificate authentication
... OpenSSL, not version 0.9.8h because that seems to suffer from a bug which doesn't allow you to properly generate PKCS#12 files.
This PKCS#12 file will be used by the Java client to present the client certificate to the server when the server has explicitly requested the client to authenticate. See...
How is “mvn clean install” different from “mvn install”?
...hought of as an action or task) in Maven. mvn clean install tells Maven to do the clean phase in each module before running the install phase for each module.
What this does is clear any compiled files you have, making sure that you're really compiling each module from scratch.
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How to change value of process.env.PORT in node.js?
I'd like to change the value of process.env.PORT , how can I do this?
4 Answers
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Changing column names of a data frame
...l_count = count / 482462) results in the error Error in mutate_impl(.data, dots) : unknown column 'days' (where days is a new name given to the column). This is really frustrating.
– David Tonhofer
Feb 7 '17 at 21:19
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Decorators with parameters?
...m with the transfer of variable 'insurance_mode' by the decorator. I would do it by the following decorator statement:
13 A...