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SQL JOIN and different types of JOINs
... and start with cross join and then "build" inner join on top of it. After all, the mere concept of cross join invalidates these informal and inaccurate Venn diagram visualisations...
– Lukas Eder
Apr 21 '17 at 17:25
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Polymorphism vs Overriding vs Overloading
...xample when teaching a class. The canonical "Bank Account" class didn't really express the "abstractness" of the base class. The other canonical example (Animal, make noise) was too abstract for understanding. I was looking for a single base with too obvious subclasses. Actually, goPee() was the...
Why generate long serialVersionUID instead of a simple 1L?
...when trying to deserialize an object.
If the ID is omitted, Java will actually calculate the ID for you based on fields of the object, but I believe it is an expensive process, so providing one manually will improve performance.
Here's are a couple of links to articles which discuss serialization ...
Remove specific characters from a string in Python
...the answers, and it's noted in the documentation for str.translate.
When calling the translate method of a Unicode string, you cannot pass the second parameter that we used above. You also can't pass None as the first parameter. Instead, you pass a translation table (usually a dictionary) as the on...
ASP.NET MVC 3 Razor - Adding class to EditorFor
...ating issue, and I didn't want to create an EditorTemplate that applied to all DateTime values (there were times in my UI where I wanted to display the time and not a jQuery UI drop-down calendar). In my research, the root issues I came across were:
The standard TextBoxFor helper allowed me to app...
Interfaces vs. abstract classes [duplicate]
...o functions
Have slightly more control in how the "interface" methods are called
Ability to provide behavior related or unrelated to the interface for "free"
Interfaces are merely data passing contracts and do not have these features. However, they are typically more flexible as a type can only be...
Career day in kindergarten: how to demonstrate programming in 20 minutes? [closed]
...a lot of paper towels on a table, and got out a loaf of (cheap) bread, a small tub of butter, a small jar of jelly, and a plastic butter knife.
I said to the kids, "How many of you think computers are smart?" Most of them raised their hands. I said, "Computers are really dumb. People are smart. ...
How to delete all data from solr and hbase
How do I delete all data from solr by command? We are using solr with lily and hbase .
18 Answers
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Compiler Ambiguous invocation error - anonymous method and method group with Func or Action
... method group syntax rather than anonymous methods (or lambda syntax) for calling a function.
4 Answers
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How do I remove the old history from a git repository?
...mple.com>
Date: Thu May 23 22:27:48 2013 +0200
Some message
If all looks as intended, you can just do a simple git filter-branch -- --all to make it permanent.
BEWARE: after doing the filter-branch step, all commit ids will have changed, so anybody using the old repo must never merge w...