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Array.Copy vs Buffer.BlockCopy
...Copy() can perform very poorly here due to the continual "safe" value type casting, compared to the direct casting of Buffer.BlockCopy().
Additional evidence from outside StackOverflow that Array.Copy() is faster than Buffer.BlockCopy() for same-type array copying can be found here.
...
How to get current time in milliseconds in PHP?
... decimals
1409263371904
Note that both $mt[1] and the result of round are casted to int. This is necessary because they are floats and the operation on them without casting would result in the function returning a float.
Finally, that function is slightly more precise than
round(microtime(true)*100...
Why doesn't Java allow generic subclasses of Throwable?
...
Yes, but why isn't it flagged as "unsafe" then, as with casts for example?
– eljenso
Feb 1 '09 at 19:17
...
How can one print a size_t variable portably using the printf family?
...ode into a file that's compiled as C99. Otherwise, your only option is to cast your variables to unsigned long long and use %llu to be maximally portable.
– Adam Rosenfield
Apr 13 '10 at 1:52
...
MySQL error: key specification without a key length
...r BLOB types such as TINYBLOB, MEDIUMBLOB, LONGBLOB, TINYTEXT, MEDIUMTEXT, and LONGTEXT that you try to make a primary key or index. With full BLOB or TEXT without the length value, MySQL is unable to guarantee the uniqueness of the column as it’s of variable and dynamic size. So, when using BLOB ...
How to create a SQL Server function to “join” multiple rows from a subquery into a single delimited
... 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 [Vehicle]
It's a lot easier than using a cursor, and s...
PostgreSQL return result set as JSON array?
...t them:
SELECT to_jsonb(array_agg(t)) FROM t
or combine json_agg with a cast:
SELECT json_agg(t)::jsonb FROM t
My testing suggests that aggregating them into an array first is a little faster. I suspect that this is because the cast has to parse the entire JSON result.
9.2
9.2 does not have ...
C# - Keyword usage virtual+override vs. new
...a Bar, but we are storing it in a variable of type Foo (this is similar to casting it)
Then the result will be as follows, depending on whether you used virtual/override or new when declaring your classes.
share
...
HMAC-SHA1 in bash
...ctly what you're asking for, but there's no point in reinventing the wheel and writing a bash version.
You can simply use the openssl command to generate the hash within your script.
[me@home] echo -n "value" | openssl dgst -sha1 -hmac "key"
57443a4c052350a44638835d64fd66822f813319
Or simply:
[...
Calling Java varargs method with single null argument?
...ray. For a single argument it assumes the latter.
You have two choices. Cast the null explicitly to Object or call the method using a strongly typed variable. See the example below:
public class Temp{
public static void main(String[] args){
foo("a", "b", "c");
foo(null, null);
...