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Sqlite primary key on multiple columns
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@pratnala In standard SQL, yes. In SQLite, NULL is allowed in primary keys. This answer emphasizes that if you want more standard behavior, you need to add the NOT NULL yourself. My answer is just the very basic syntax for a multi-column primary key.
– B...
How do I change the background color of a plot made with ggplot2
...s the theme_bw, giving you a white background and grey gridlines. I use it all the time, as in print it looks much better than the default grey background: myplot + theme_bw()
– ROLO
Dec 16 '11 at 9:11
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How can I get a Dialog style activity window to fill the screen?
...tivity with the dialog theme set, and I want it to be full screen. I tried all sorts of things, even going through the WindowManager to expand the window to full width and height manually, but nothing works.
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What is the usefulness of `enable_shared_from_this`?
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It enables you to get a valid shared_ptr instance to this, when all you have is this. Without it, you would have no way of getting a shared_ptr to this, unless you already had one as a member. This example from the boost documentation for enable_shared_from_this:
class Y: public enable_s...
Should I hash the password before sending it to the server side?
...atly however, and should be used in any authenticated session.
There is really no need to know what an original password is. All that is required is a reliable way to generate (and reliably re-generate) an authentication "key" based on the original text chosen by the user. In an ideal world this ...
Evil Mode best practice? [closed]
...ided that it meets my demand for speedy movement well enough that I can finally move on to Emacs.
7 Answers
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How do I disable the resizable property of a textarea?
... elements:
textarea {
resize: none;
}
To disable it for some (but not all) textareas, there are a couple of options.
To disable a specific textarea with the name attribute set to foo (i.e., <textarea name="foo"></textarea>):
textarea[name=foo] {
resize: none;
}
Or, using an id...
Defining an abstract class without any abstract methods
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Of course.
Declaring a class abstract only means that you don't allow it to be instantiated on its own.
Declaring a method abstract means that subclasses have to provide an implementation for that method.
The two are separate concepts, though obviously you can't have an abstract method ...
Is it possible to set a number to NaN or infinity?
...question over a second time!! Sorry! That said, it wouldn't hurt to say so all the same because it's an easy trap to fall into, NaN != NaN
– David Heffernan
Mar 25 '11 at 22:30
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Error 1046 No database Selected, how to resolve?
...he SQL Development heading of the Workbench splash screen.
Addendum
This all assumes there's a database you want to create the table inside of - if not, you need to create the database before anything else:
CREATE DATABASE your_database;
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