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Get last element of Stream/List in a one-liner
...akes a point, further the API documentation states that reduce("", String::concat) is an inefficient but correct solution for string concatenation, which implies maintenance of the encounter order.The intention is well-known,the documentation has to catch up.
– Holger
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Count the occurrences of DISTINCT values
...as an aggregate function works on the entire dataset, suming, counting, or concating the specified field down to one row. Group by subdivides the dataset into chunks based on unique combos of the specified fields
– Avatar_Squadron
Aug 24 '12 at 16:37
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Why doesn't Dictionary have AddRange?
...hods let you pass in IEqualityComparer when relevant: var combined = dict1.Concat(dict2).GroupBy(kvp => kvp.Key, dict1.Comparer).ToDictionary(grp => grp.Key, grp=> grp.First(), dict1.Comparer);
– Kyle McClellan
Mar 20 '18 at 19:32
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Which is the preferred way to concatenate a string in Python?
Since Python's string can't be changed, I was wondering how to concatenate a string more efficiently?
12 Answers
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Are string.Equals() and == operator really same? [duplicate]
...ntern pool of course due to b; but a would be the result of calling String.Concat("Hell", "o");
– Jon Skeet
Sep 9 '10 at 20:54
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How to merge 2 List and removing duplicate values from it in C#
...excludes duplicates from the return set. This is different
behavior to the Concat
method, which returns all the elements
in the input sequences including
duplicates.
List<int> list1 = new List<int> { 1, 12, 12, 5};
List<int> list2 = new List<int> { 12, 5, 7, 9, 1 };
List<...
String vs. StringBuilder
...ance difference is significant. See the KB article "How to improve string concatenation performance in Visual C#".
I have always tried to code for clarity first, and then optimize for performance later. That's much easier than doing it the other way around! However, having seen the enormous perfo...
Is there any difference between GROUP BY and DISTINCT
...s. Use GROUPY BY if you want to apply aggregate operators (MAX, SUM, GROUP_CONCAT, ..., or a HAVING clause).
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Is there any JSON Web Token (JWT) example in C#?
...ify)
{
var bytesToSign = Encoding.UTF8.GetBytes(string.Concat(header, ".", payload));
var keyBytes = Encoding.UTF8.GetBytes(key);
var algorithm = (string)headerData["alg"];
var signature = HashAlgorithms[GetHashAlgorithm(algorithm)](keyBytes, ...
Stop Excel from automatically converting certain text values to dates
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In my MySQL query (for CSV output through PHP), I used CONCAT('\t', column_name). Also did the trick. Thanks!
– Just Plain High
Jun 24 '16 at 14:39
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