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Task not serializable: java.io.NotSerializableException when calling function outside closure only o
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RDDs extend the Serialisable interface, so this is not what's causing your task to fail. Now this doesn't mean that you can serialise an RDD with Spark and avoid NotSerializableException
Spark is a distributed computing engine and its main abstraction i...
Difference between shadowing and overriding in C#?
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Well inheritance...
suppose you have this classes:
class A {
public int Foo(){ return 5;}
public virtual int Bar(){return 5;}
}
class B : A{
public new int Foo() { return 1;} //shadow
public override int Bar() {return 1;} //override
}
then when you call this:
A clA = new A();
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How to implement one-to-one, one-to-many and many-to-many relationships while designing tables?
... # "link back" if you need
You must also put a unique constraint on the foreign key column (addess.student_id) to prevent multiple rows in the child table (address) from relating to the same row in the referenced table (student).
One-to-many: Use a foreign key on the many side of the ...
What is the exact problem with multiple inheritance?
...people asking all the time whether multiple inheritance should be included into the next version of C# or Java. C++ folks, who are fortunate enough to have this ability, say that this is like giving someone a rope to eventually hang themselves.
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Should I use string.isEmpty() or “”.equals(string)?
...always wondering why others use this so often, but didn't take null values into account. Great :-)
– Peter Wippermann
Dec 2 '10 at 10:51
10
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How to write WinForms code that auto-scales to system font and dpi settings?
... designer won't rescale on high DPI monitor), and in code read that value, convert from pixels to points (to get correct scaling).
– ToolmakerSteve
Aug 13 '17 at 11:03
1
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What is a “static” function in C?
...+ methods are often referred to as "member functions", so I agree that C++ introduces a little bit of ambiguity. It's not your fault — the language just uses the keyword for two different things.
– Chuck
Feb 17 '09 at 18:40
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ORDER BY the IN value list
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You can do it quite easily with (introduced in PostgreSQL 8.2) VALUES (), ().
Syntax will be like this:
select c.*
from comments c
join (
values
(1,1),
(3,2),
(2,3),
(4,4)
) as x (id, ordering) on c.id = x.id
order by x.ordering
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How to get the filename without the extension in Java?
...brary solution above. It works, but looking at the code (without having to interpret the REGEX) isn't obvious what it does.
– Gustavo Litovsky
Nov 28 '12 at 21:12
5
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How to get parameters from the URL with JSP
...tlet:
<%
if (request.getParameter("name") == null) {
out.println("Please enter your name.");
} else {
out.println("Hello <b>"+request. getParameter("name")+"</b>!");
}
%>
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