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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 ...
How to solve PHP error 'Notice: Array to string conversion in…'
...n $_POST['C']. So when you echo that, you are trying to print an array, so all it does is print Array and a notice.
To print properly an array, you either loop through it and echo each element, or you can use print_r.
Alternatively, if you don't know if it's an array or a string or whatever, you c...
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;
...
How do I run a Python program in the Command Prompt in Windows 7?
...Python27). See below for exact steps.
The PATH environment variable lists all the locations that Windows (and cmd.exe) will check when given the name of a command, e.g. "python" (it also uses the PATHEXT variable for a list of executable file extensions to try). The first executable file it finds o...
UTF-8 byte[] to String
... You can see in here the java.nio.charset.Charset.availableCharsets() map all the charsets not just the charsets in the StandardCharsets. And if you want to use some other charset and still want to prevent the String constructor from throwing UnsupportedEncodingException you may use java.nio.charse...
Create a List of primitive int?
... add "int" into this list.
When you add int to this list, it is automatically boxed to Integer wrapper type. But it is a bad idea to use raw type lists, or for any generic type for that matter, in newer code.
I can add anything into this list.
Of course, that is the dis-advantage of using r...
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 do I replace multiple spaces with a single space in C#?
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I have copy and paste that and it works. I really do not like REgex but this time it saves my life.
– Pokus
Oct 15 '08 at 22:22
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What is the use of GO in SQL Server Management Studio & Transact SQL?
...te a query using the right click "Script As" menu. Why? What does GO actually do?
7 Answers
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Set line spacing
...equires ᴜᴅᴘ socket (because of the lost of ɴᴘᴀᴘɪ support and all browsers are withdrawing support in their custom plug‑in ᴀᴘɪ). The ᴊᴘʟ web site dedicated to the Cassini mission still requires the quick time plugin in order to watch their videoꜱ online. Not to mention onl...