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MySQL: Order by field size/length
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SELECT * FROM TEST ORDER BY LENGTH(description) DESC;
The LENGTH function gives the length of string in bytes. If you want to count (multi-byte) characters, use the CHAR_LENGTH function instead:
SELECT * FROM TEST ORDER BY...
Java: notify() vs. notifyAll() all over again
...and the difference between these methods right), only one thread is always selected for further monitor acquisition.
That is not correct. o.notifyAll() wakes all of the threads that are blocked in o.wait() calls. The threads are only allowed to return from o.wait() one-by-one, but they each will...
How do I specify a pointer to an overloaded function?
...putIterator, InputIterator, UnaryFunction );
Template deduction needs to select a type for UnaryFunction at the point of the call. But f doesn't have a specific type - it's an overloaded function, there are many fs each with different types. There is no current way for for_each to aid the template...
Remove characters from C# string
... where char.IsWhiteSpace(c) || char.IsLetterOrDigit(c)
select c
).ToArray());
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How to use GROUP BY to concatenate strings in SQL Server?
...S (1,'B',8)
INSERT INTO #YourTable ([ID],[Name],[Value]) VALUES (2,'C',9)
SELECT
[ID],
STUFF((
SELECT ', ' + [Name] + ':' + CAST([Value] AS VARCHAR(MAX))
FROM #YourTable
WHERE (ID = Results.ID)
FOR XML PATH(''),TYPE).value('(./text())[1]','VARCHAR(MAX)')
,1,2,'') AS NameVa...
How can I reliably determine the type of a variable that is declared using var at design time?
...o resolve the type. For instance:
var items = myList.OfType<Foo>().Select(foo => foo.Bar);
The return type is IEnumerable<Bar>, but resolving this required knowing:
myList is of type that implements IEnumerable.
There is an extension method OfType<T> that applies to IEnume...
LINQ: “contains” and a Lambda query
...Here is how you can use Contains to achieve what you want:
buildingStatus.Select(item => item.GetCharValue()).Contains(v.Status) this will return a Boolean value.
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MySQL - length() vs char_length()
... in two bytes. Or UTF-8, where the number of bytes varies. For example:
select length(_utf8 '€'), char_length(_utf8 '€')
--> 3, 1
As you can see the Euro sign occupies 3 bytes (it's encoded as 0xE282AC in UTF-8) even though it's only one character.
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How to convert an entire MySQL database characterset and collation to UTF-8?
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You can create the sql to update all tables with:
SELECT CONCAT("ALTER TABLE ",TABLE_SCHEMA,".",TABLE_NAME," CHARACTER SET utf8 COLLATE utf8_general_ci; ",
"ALTER TABLE ",TABLE_SCHEMA,".",TABLE_NAME," CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci; ")
AS a...
How to create a SQL Server function to “join” multiple rows from a subquery into a single delimited
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If you're using SQL Server 2005, you could use the FOR XML PATH command.
SELECT [VehicleID]
, [Name]
, (STUFF((SELECT CAST(', ' + [City] AS VARCHAR(MAX))
FROM [Location]
WHERE (VehicleID = Vehicle.VehicleID)
FOR XML PATH ('')), 1, 2, '')) AS Locations
FROM [...