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Change auto increment starting number?
... DECLARE _stmt VARCHAR(1024);
SET @inc := 0;
SET @MAX_SQL := CONCAT('SELECT IFNULL(MAX(`id`), 0) + 1 INTO @inc FROM ', _table);
PREPARE _max_stmt FROM @MAX_SQL;
EXECUTE _max_stmt;
DEALLOCATE PREPARE _max_stmt;
SET @SQL := CONCAT('ALTER TABLE ', _table, ' AUTO_INCREMENT...
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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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...
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...
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...
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...
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 ...