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How to merge a list of lists with same type of items to a single list of items?
...es, convert each TSource in the list into an IEnumerable of TResults, then concatenate all those IEnumerables into one big one. In this case you have a list of lists to start, so if you want to concatenate them the function to map from a TSource (which is an IEnumerable of TResults) to an IEnumerabl...
C# Thread safe fast(est) counter
...al++;
} while (midpointCount < 50000);
Interlocked.Add(ref totalCount, total);
Interlocked.Add(ref totalMidpoint, midpt);
string s = String.For...
How to do a regular expression replace in MySQL?
...= SUBSTRING(original,i,1);
IF NOT ch REGEXP pattern THEN
SET temp = CONCAT(temp,ch);
ELSE
SET temp = CONCAT(temp,replacement);
END IF;
SET i=i+1;
END LOOP;
ELSE
SET temp = original;
END IF;
RETURN temp;
END$$
DELIMITER ;
Example execution:
mysql> select regex_replac...
How to create a video from images with FFmpeg?
....txt like below.
# this is a comment details https://trac.ffmpeg.org/wiki/Concatenate
file 'E:\images\png\images__%3d.jpg'
file 'E:\images\jpg\images__%3d.jpg'
Sample usage as follows;
"h:\ffmpeg\ffmpeg.exe" -y -r 1/5 -f concat -safe 0 -i "E:\images\imagepaths.txt" -c:v libx264 -vf "fps=25,form...
GROUP BY with MAX(DATE) [duplicate]
...t try this...
SELECT
`Train`,
`Dest`,
SUBSTRING_INDEX(GROUP_CONCAT(`Time` ORDER BY `Time` DESC), ",", 1) AS `Time`
FROM TrainTable
GROUP BY Train;
Src: Group Concat Documentation
Edit: fixed sql syntax
shar...
Append TimeStamp to a File Name
...c string AppendTimeStamp(this string fileName)
{
return string.Concat(
Path.GetFileNameWithoutExtension(fileName),
DateTime.Now.ToString("yyyyMMddHHmmssfff"),
Path.GetExtension(fileName)
);
}
}
...
Reason for Column is invalid in the select list because it is not contained in either an aggregate f
...
@davidblaine, MySQL has a function GROUP_CONCAT() for that. dev.mysql.com/doc/refman/5.5/en/… But in standard SQL, each column should contain only one value. That's fundamental to relational theory too.
– Bill Karwin
Dec 22...
Prefer composition over inheritance?
...ny = new Person ("Mr.", "John", 25);
Employee john = new Employee (johnny, 50000);
Composition is typically "has a" or "uses a" relationship. Here the Employee class has a Person. It does not inherit from Person but instead gets the Person object passed to it, which is why it "has a" Person.
Comp...
Cosmic Rays: what is the probability they will affect a program?
...ome cases from alpha-emitters inside PC. BH authors did experiment and got 50000 accesses to domains, having 1 bit changed from popular sites
– osgx
May 14 '14 at 10:45
...
Java Programming - Where should SQL statements be stored? [closed]
...endor lock-in in the java world is interesting.
I hope you haven't paid $50000 pr CPU for Oracle Enterprise, and then only used the least common denominator in order to switch to Mysql any minute. As any good DBA will tell you, there are subtle differences between the different big name databases,...