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Identity increment is jumping in SQL Server database
... since SQL Server 2012.
It now by default uses a cache size of 1,000 when allocating IDENTITY values for an int column and restarting the service can "lose" unused values (The cache size is 10,000 for bigint/numeric).
This is mentioned in the documentation
SQL Server might cache identity valu...
Read whole ASCII file into C++ std::string [duplicate]
...lts.
Following KeithB's point in the comments, here's a way to do it that allocates all the memory up front (rather than relying on the string class's automatic reallocation):
#include <string>
#include <fstream>
#include <streambuf>
std::ifstream t("file.txt");
std::string str;...
How to make MySQL handle UTF-8 properly
...taking extra storage when most text is ASCII. Although char strings are preallocated, varchar strings are not -- see the last few lines on this documentation page. For example, char(10) will be pessimistically reserve 40 bytes under utf8mb4, but varchar(10) will allocate bytes in keeping with the v...
Is it better to return null or empty collection?
...t;() instead of a new Foo[0]. It is more explicit and saves you one memory allocation (at least, in my installed .NET implementation).
– Trillian
Dec 28 '09 at 20:47
4
...
capturing self strongly in this block is likely to lead to a retain cycle
...RING YOU TO RETAIN LOOP
}
};
and don't forget to do:
- (void)dealloc {
self.loadingCompletionHandler = NULL;
}
another issue can appear if you will pass weak copy of not retained by anybody object:
MyViewController *vcToGo = [[MyViewCOntroller alloc] init];
__weak MyViewController...
How do I show a console output/window in a forms application?
...nteropServices;
private void Form1_Load(object sender, EventArgs e)
{
AllocConsole();
}
[DllImport("kernel32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool AllocConsole();
share...
What is JavaScript garbage collection?
...ier
post.)
At this point we know that all the
memory still marked is allocated
memory which cannot be reached by any
path from any in-scope variable. All
of those objects are instructed to
tear themselves down, which destroys
any circular references.
The main purpose of garbage...
Setting variable to NULL after free
... int *nPtr=NULL;. Now, I would agree that this would be redundant, with a malloc following right in the next line. However, if there is code between the declaration and the first initialization, somebody might start using the variable even though it has no value yet. If you null-initialize, you get ...
Java Equivalent of C# async/await?
... = AsynchronousFileChannel.open(path);
ByteBuffer buffer = ByteBuffer.allocate(100_000);
await channel.read(buffer, 0, buffer, this);
return buffer.get(0);
}
Then I would imagine the compiler will transform the original async/await code into something like this:
public static Future&...
What is a “cache-friendly” code?
...ilar processors. In some cases, however, it can be worth doing things like allocating a large buffer, and then using only parts of what you allocated to ensure against data sharing the same cache lines (even though you'll probably need to detect the exact processor and act accordingly to do this).
...