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Difference between Node object and Element object?
I am totally confused between Node object and Element object.
document.getElementById() returns Element object while document.getElementsByClassName()
returns NodeList object(Collection of Elements or Nodes?)
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How do I perform the SQL Join equivalent in MongoDB?
...t array field>
}
}
Of course Mongo is not a relational database, and the devs are being careful to recommend specific use cases for $lookup, but at least as of 3.2 doing join is now possible with MongoDB.
share
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append multiple values for one key in a dictionary [duplicate]
I am new to python and I have a list of years and values for each year. What I want to do is check if the year already exists in a dictionary and if it does, append the value to that list of values for the specific key.
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What are the most common SQL anti-patterns? [closed]
...d (or are learning) that SQL is different. Eliciting the desired results, and doing so efficiently, involves a tedious process partly characterized by learning unfamiliar paradigms, and finding out that some of our most familiar programming patterns don't work here. What are the common antipattern...
How to print colored text in Python?
...Continue?{bcolors.ENDC}")
This will work on unixes including OS X, linux and windows (provided you use ANSICON, or in Windows 10 provided you enable VT100 emulation). There are ansi codes for setting the color, moving the cursor, and more.
If you are going to get complicated with this (and it sou...
HashMap get/put complexity
...tant time... but you could have a hash which takes a long time to compute, and if there are multiple items in the hash map which return the same hash code, get will have to iterate over them calling equals on each of them to find a match.
In the worst case, a HashMap has an O(n) lookup due to walki...
Cannot use identity column key generation with ( TABLE_PER_CLASS )
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The problem here is that you mix "table-per-class" inheritance and GenerationType.Auto.
Consider an identity column in MsSQL. It is column based. In a "table-per-class" strategy you use one table per class and each one has an ID.
Try:
@GeneratedValue(strategy = GenerationType.TABLE)
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Shortcut to comment out a block of code with sublime text
...or uncomment the selected text or current line:
Windows: Ctrl+/
Mac: Command ⌘+/
Linux: Ctrl+Shift+/
Alternatively, use the menu: Edit > Comment
For the block comment you may want to use:
Windows: Ctrl+Shift+/
Mac: Command ⌘+Option/Alt+/
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Override Java System.currentTimeMillis for testing time sensitive code
...commend that instead of messing with the system clock, you bite the bullet and refactor that legacy code to use a replaceable clock. Ideally that should be done with dependency injection, but even if you used a replaceable singleton you would gain testability.
This could almost be automated with se...
What's the use of session.flush() in Hibernate
...) I have class where I am saving object using code id = session.save(obj); and transaction is committed at very next line but obj is not getting saved to DB ,Why? 2) I saved obj using session.save(obj); with commit and while returning I used return obj.getprimaryID(); In this case obj is saved to DB...