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How to split a comma-separated value to columns
...his should not be the accepted answer... A multi-statement TVF (very bad!) and a WHILE loop (even worse) together will perform awfully. Besides, this is a code-only answer and does not even solve the issue There are much better approaches around! For SQL-Server 2016+ look for STRING_SPLIT() (which d...
(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...
Difference between HashSet and HashMap?
... does not allow duplicate values, what is the difference between HashMap and HashSet ?
19 Answers
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The tilde operator in C
I've seen the tilde operator used in the ELF hashing algorithm, and I'm curious what it does. (The code is from Eternally Confused .)
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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...
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...
counting number of directories in a specific directory
...he number of folders in a specific directory. I am using the following command, but it always provides an extra one.
15 An...
The 'json' native gem requires installed build tools
...on my windows 7 machine. Now I tried to install the JSON gem using the command, "gem install json" and got the following error.
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Why all the Active Record hate? [closed]
As I learn more and more about OOP, and start to implement various design patterns, I keep coming back to cases where people are hating on Active Record .
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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...