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What is the string concatenation operator in Oracle?
What is the string concatenation operator in Oracle SQL?
5 Answers
5
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Joining two lists together
...e list a. If you wanted to preserve the original lists then you should use Concat (as pointed out in the other answers):
var newList = a.Concat(b);
This returns an IEnumerable as long as a is not null.
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How can I concatenate two arrays in Java?
I need to concatenate two String arrays in Java.
61 Answers
61
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Merge two (or more) lists into one, in C# .NET
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You can use the LINQ Concat and ToList methods:
var allProducts = productCollection1.Concat(productCollection2)
.Concat(productCollection3)
.ToList();
Note that there are ...
Simulating group_concat MySQL function in Microsoft SQL Server 2005?
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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
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How do you use the “WITH” clause in MySQL?
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declare recursive_table_tmp varchar(120);
set recursive_table_next = concat(recursive_table, "_next");
set recursive_table_union = concat(recursive_table, "_union");
set recursive_table_tmp = concat(recursive_table, "_tmp");
# Cleanup any previous failed runs
SET @str =
CONCAT("...
How to remove leading and trailing whitespace in a MySQL field?
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I downvoted. Testcase: SELECT CONCAT('"', TRIM(" hello world "), '"') AS `trimmed value` FROM DUAL gives the wanted output "hello world". While the replace variant dangerously removes the space as word separator: SELECT CONCAT('"', REPLACE(" hello world "...
How to append something to an array?
...ant to add the items of one array to another array, you can use firstArray.concat(secondArray):
var arr = [
"apple",
"banana",
"cherry"
];
arr = arr.concat([
"dragonfruit",
"elderberry",
"fig"
]);
console.log(arr);
Update
Just an addition to this answer if you want to prepend...
GROUP_CONCAT comma separator - MySQL
I have a query where I am using GROUP_CONCAT and a custom separator as my results may contain commas: '----'
3 Answers
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Is there a performance gain in using single quotes vs double quotes in ruby?
... x.report("assign double") { n.times do; c = "a string"; end}
x.report("concat single") { n.times do; 'a string ' + 'b string'; end}
x.report("concat double") { n.times do; "a string " + "b string"; end}
end
$ ruby benchmark_quotes.rb
user system total r...