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mmap() vs. reading blocks
...r random access, especially if your access patterns are sparse and unpredictable.
Memory maps allow you to keep using pages from the cache until you are done. This means that if you use a file heavily for a long period of time, then close it and reopen it, the pages will still be cached. With read...
UITableView - scroll to the top
In my table view I have to scroll to the top. But I cannot guarantee that the first object is going to be section 0, row 0. May be that my table view will start from section number 5.
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How to convert boost path type to string?
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@MarcoAlka See the linked table boost.org/doc/libs/1_48_0/libs/filesystem/v3/doc/… and note the second line: class path canonize() Function removed - that means it was once in the library but no longer--the definition of deprecated.
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How to efficiently build a tree from a flat structure?
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Store IDs of the objects in a hash table mapping to the specific object. Enumerate through all the objects and find their parent if it exists and update its parent pointer accordingly.
class MyObject
{ // The actual object
public int ParentID { get; set; ...
How does std::forward work? [duplicate]
...thing using another mysterious thing. This particular cast is defined by a table in Xeo's answer. But the question is: Why? So here's my understanding:
Suppose I want to pass you an std::vector<T> v that you're supposed to store in your data structure as data member _v. The naive (and safe) s...
Code Golf: Lasers
...&redo}die/x/?true:false,$/
The first line loads the input into %t, a table of the board where $t{99*i+j} holds the character at row i,column j. Then,
%d=split//,'>.^1<2v3' ; ($r)=grep{$d|=$d{$t{$_}}}%t
it searches the elements of %t for a character that matches > ^ < or v, and s...
Using IQueryable with Linq
...tabase, with many ORM systems, you have the option of fetching data from a table in two ways, one which returns IEnumerable<T>, and one which returns an IQueryable<T>. Say, for example, you have a Products table, and you want to get all of the products whose cost is >$25.
If you do:...
Why does C++11 not support designated initializer lists as C99? [closed]
...me it has failed
Ben Voigt's comments have helped me to see the insurmountable problems with this approach; given:
struct X {
int c;
char a;
float b;
};
What order would these functions be called in in c99: struct X foo = {.a = (char)f(), .b = g(), .c = h()}? Surprisingly, in c99:
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How do I change column default value in PostgreSQL?
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'SET' is forgotten
ALTER TABLE ONLY users ALTER COLUMN lang SET DEFAULT 'en_GB';
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Add a default value to a column through a migration
...an a change block. You can leave the down block empty. It won't revert the table to the original condition but the migration can be rolled back.
– IAmNaN
May 16 '14 at 1:16
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