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(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...
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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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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Difference between HashSet and HashMap?
... does not allow duplicate values, what is the difference between HashMap and HashSet ?
19 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...
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-...
twig: IF with multiple conditions
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If I recall correctly Twig doesn't support || and && operators, but requires or and and to be used respectively. I'd also use parentheses to denote the two statements more clearly although this isn't technically a requirement.
{%if ( fields | length > 0 ) or ...
Is there something like RStudio for Python? [closed]
In RStudio, you can run parts of code in the code editing window, and the results appear in the console.
10 Answers
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MySQL order by before group by
...t the max(post_date) by author is to use a subquery to return the max date and then join that to your table on both the post_author and the max date.
The solution should be:
SELECT p1.*
FROM wp_posts p1
INNER JOIN
(
SELECT max(post_date) MaxPostDate, post_author
FROM wp_posts
WHERE po...
How to format numbers as currency string?
...ce in JavaScript. I'd like a function which takes a float as an argument and returns a string formatted like this:
66 A...