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What is a race condition?
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A race condition occurs when two or more threads can access shared data and they try to change it at the same time. Because the thread scheduling algorithm can swap between threads at any time, you don't know the order in which the threads will attempt to access the shared data. Therefore, the re...
(this == null) in C#!
...spec (section 7.5.7), you shouldn't be able to access this in that context and the ability to do so in C# 3.0 compiler is a bug. C# 4.0 compiler is behaving correctly according to the spec (even in Beta 1, this is a compile time error):
§ 7.5.7 This access
A this-access consists of the res...
How to store arrays in MySQL?
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The proper way to do this is to use multiple tables and JOIN them in your queries.
For example:
CREATE TABLE person (
`id` INT NOT NULL PRIMARY KEY,
`name` VARCHAR(50)
);
CREATE TABLE fruits (
`fruit_name` VARCHAR(20) NOT NULL PRIMARY KEY,
`color` VARCHAR(20),
`price` INT
)...
Python syntax for “if a or b or c but not all of them”
I have a python script that can receive either zero or three command line arguments. (Either it runs on default behavior or needs all three values specified.)
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SQL Server: What is the difference between CROSS JOIN and FULL OUTER JOIN?
What is the difference between CROSS JOIN and FULL OUTER JOIN in SQL Server?
10 Answers
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How to select the nth row in a SQL database table?
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There are ways of doing this in optional parts of the standard, but a lot of databases support their own way of doing it.
A really good site that talks about this and other things is http://troels.arvin.dk/db/rdbms/#select-limit.
Basically, PostgreSQL and MySQL supports the non-...
Should unit tests be written for getter and setters?
Are we supposed to write tests for our getters and setters or is it overkill?
13 Answers
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Difference between HashSet and HashMap?
... does not allow duplicate values, what is the difference between HashMap and HashSet ?
19 Answers
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How can I calculate the difference between two dates?
How can I calculate the days between 1 Jan 2010 and (for example) 3 Feb 2010?
9 Answers
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When to use Common Table Expression (CTE)
I have begun reading about Common Table Expression and cannot think of a use case where I would need to use them. They would seem to be redundant as the same can be done with derived tables. Is there something I am missing or not understanding well? Can someone give me a simple example of limitati...