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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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String concatenation does not work in SQLite
...p>' from location;
From SQLite documentation:
The || operator is "concatenate" - it joins together the two strings of its operands.
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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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LEFT JOIN only first row
...ect only the first item in a LEFT JOIN.
You can use a subquery that GROUP_CONCATS what you want (sorted, too!), then just split the GROUP_CONCAT'd result and take only its first item, like so...
LEFT JOIN Person ON Person.id = (
SELECT SUBSTRING_INDEX(
GROUP_CONCAT(FirstName ORDER BY F...
What is the purpose of “!” and “?” at the end of method names?
... Beware, this isn't always the case. For example, Ruby Array#concat docs.ruby-lang.org/en/2.0.0/Array.html#method-i-concat. Where you can get burnt badly is something like MyActiveRecordModel.column_names.concat(...). Instead you must clone it before doing the concat.
...
How to remove leading and trailing whitespace in a MySQL field?
...
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...
Why is it Valid to Concatenate Null Strings but not to Call “null.ToString()”?
...
The reason for first one working:
From MSDN:
In string concatenation operations,the C# compiler treats a null string the same as an empty string, but it does not convert the value of the original null string.
More information on the + binary operator:
The binary + operator perf...
Oracle SQL, concatenate multiple columns + add text
...
You have two options for concatenating strings in Oracle:
CONCAT
Using ||
CONCAT example:
CONCAT(
CONCAT(
CONCAT(
CONCAT(
CONCAT('I like ', t.type_desc_column),
' cake with '),
t.icing_desc_column),
' and ...
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...