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Are JavaScript strings immutable? Do I need a “string builder” in JavaScript?
...eard what Ash mentioned in his answer (that using Array.join is faster for concatenation) so I wanted to test out the different methods of concatenating strings and abstracting the fastest way into a StringBuilder. I wrote some tests to see if this is true (it isn't!).
This was what I believed woul...
Simulating group_concat MySQL function in Microsoft SQL Server 2005?
...
This only shows how to concat values - group_concat concats them by group, which is more challenging (and what the OP appears to require). See the accepted answer to SO 15154644 for how to do this - the WHERE clause is the critical addition
...
Most efficient way to concatenate strings?
What's the most efficient way to concatenate strings?
17 Answers
17
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MySQL Results as comma separated list
...
You can use GROUP_CONCAT to perform that, e.g. something like
SELECT p.id, p.name, GROUP_CONCAT(s.name) AS site_list
FROM sites s
INNER JOIN publications p ON(s.id = p.site_id)
GROUP BY p.id, p.name;
...
How do I concatenate multiple C++ strings on one line?
C# has a syntax feature where you can concatenate many data types together on 1 line.
24 Answers
...
How can I concatenate two arrays in Java?
I need to concatenate two String arrays in Java.
61 Answers
61
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How do you convert a byte array to a hexadecimal string, and vice versa?
...1.1X faster)
Sentence: 17.95 (2.2X faster)
Array.ConvertAll (using string.Concat, requires .NET 4.0) (via Will Dean)
Text: 752,078.70 (1.0X faster)
Sentence: 18.28 (2.2X faster)
{StringBuilder}.AppendFormat (using foreach) (via Tomalak)
Text: 672,115.77 (1.1X faster)
Sentence: 36.82 (1.1X fast...
How to change the CHARACTER SET (and COLLATION) throughout a database?
...8. Hope this helps!
-- Change DATABASE Default Collation
SELECT DISTINCT concat('ALTER DATABASE `', TABLE_SCHEMA, '` CHARACTER SET utf8 COLLATE utf8_unicode_ci;')
from information_schema.tables
where TABLE_SCHEMA like 'database_name';
-- Change TABLE Collation / Char Set
SELECT concat('ALTER T...
Remove characters from C# string
...ets)));
p.Add(string.Join(" ", title, "LinqSplit"), n => String.Concat(sample.Select(c => targets.Contains(c) ? replacement : new string(c, 1))));
p.Add(string.Join(" ", title, "Regex"), n => Regex.Replace(sample, tox, replacement));
p.Add(string.Join(" ", title, "Re...
MySQL stored procedure vs function, which would I use when?
...TE FUNCTION hello (s CHAR(20))
RETURNS CHAR(50) DETERMINISTIC
RETURN CONCAT('Hello, ',s,'!');
Query OK, 0 rows affected (0.00 sec)
CREATE TABLE names (id int, name varchar(20));
INSERT INTO names VALUES (1, 'Bob');
INSERT INTO names VALUES (2, 'John');
INSERT INTO names VALUES (3, 'Paul');
S...