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Selecting the last value of a column
...spreadsheet with some values in column G. Some cells are empty in between, and I need to get the last value from that column into another cell.
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Overriding the java equals() method - not working?
I ran into an interesting (and very frustrating) issue with the equals() method today which caused what I thought to be a well tested class to crash and cause a bug that took me a very long time to track down.
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Sort objects in ArrayList by date?
...MyObject o) {
return getDateTime().compareTo(o.getDateTime());
}
}
And then you sort it by calling:
Collections.sort(myList);
However sometimes you don't want to change your model, like when you want to sort on several different properties. In that case, you can create comparator on the f...
Get records with max value for each group of grouped SQL results
...alue for.
You avoid complicated subqueries that try to find the max() etc, and also the problems of returning multiple rows when there are more than one with the same maximum value (as the other answers would do)
Note: This is a mysql-only solution. All other databases I know will throw an SQL synta...
Value cannot be null. Parameter name: source
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I had this one a while back, and the answer isn't necessarily what you'd expect. This error message often crops up when your connection string is wrong.
At a guess, you'll need something like this:
<connectionStrings>
<add name="hublisherE...
How does HTTP file upload work?
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Let's take a look at what happens when you select a file and submit your form (I've truncated the headers for brevity):
POST /upload?upload_progress_id=12344 HTTP/1.1
Host: localhost:3000
Content-Length: 1325
Origin: http://localhost:3000
... other headers ...
Content-Type: multip...
JavaScript string encryption and decryption?
I'm interested in building a small app for personal use that will encrypt and decrypt information on the client side using JavaScript. The encrypted information will be stored in a database on a server, but never the decrypted version.
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Pass arguments to Constructor in VBA
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Here's a little trick I'm using lately and brings good results. I would like to share with those who have to fight often with VBA.
1.- Implement a public initiation subroutine in each of your custom classes. I call it InitiateProperties throughout all my classes....
How to prevent the activity from loading twice on pressing the button
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In the button's event listener, disable the button and show another activity.
Button b = (Button) view;
b.setEnabled(false);
Intent i = new Intent(this, AnotherActitivty.class);
startActivity(i);
Override onResume() to re-enable the button.
@Override
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Difference between `constexpr` and `const`
What's the difference between constexpr and const ?
9 Answers
9
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