大约有 13,800 项符合查询结果(耗时:0.0174秒) [XML]
How to work around the lack of transactions in MongoDB?
...- they'll be multi-statement, with similar semantics and syntax (like start_transaction and commit_transaction). Importantly, the changes to MongoDB that enable transactions do not impact performance for workloads that do not require them.
For more details see here.
Having distributed transaction...
Is there any difference between the `:key => “value”` and `key: “value”` hash notations?
...Hash keys are "simple" symbols (more or less something that matches /\A[a-z_]\w*\z/i, AFAIK the parser uses its label pattern for these keys).
The :$in style symbols show up a fair bit when using MongoDB so you'll end up mixing Hash styles if you use MongoDB. And, if you ever work with specific key...
Split comma-separated strings in a column into separate rows
...brary(magrittr)
Define function for benchmark runs of problem size n
run_mb <- function(n) {
# compute number of benchmark runs depending on problem size `n`
mb_times <- scales::squish(10000L / n , c(3L, 100L))
cat(n, " ", mb_times, "\n")
# create data
DF <- data.frame(directo...
Path of assets in CSS files in Symfony 2
... 14 combinations on the same twig, and this route was launched from
"/app_dev.php/"
"/app.php/"
and "/"
thus giving 14 x 3 = 42 tests.
Additionally, all this has been tested working in a subdirectory, so there is no way to fool by giving absolute URLs because they would simply not work.
The te...
Is there a way to check if a file is in use?
...tem.Runtime.InteropServices;
internal static class Helper
{
const int ERROR_SHARING_VIOLATION = 32;
const int ERROR_LOCK_VIOLATION = 33;
private static bool IsFileLocked(Exception exception)
{
int errorCode = Marshal.GetHRForException(exception) & ((1 << 16) - 1);
return errorCode...
Logger slf4j advantages of formatting with {} instead of string concatenation
...ogger,so that it avoids string concatenation?
– a3.14_Infinity
Nov 26 '14 at 10:46
add a comment
|
...
Vim: What's the difference between let and set?
...ple, this function uses let to assign the value in the global variable orig_tw to the textwidthoption:
" Toggle Autowrap
" Default of 72 but can be overridden by tw settings in other vimrc files
let g:orig_tw = 72
function Toggle_autowrap_mode()
if &textwidth == 0
" Must use let ins...
Best practices for Storyboard login screen, handling clearing of data upon logout
... return true
In Sign up view controller:
@IBAction func actionSignup(_ sender: Any) {
let appDelegateTemp = UIApplication.shared.delegate as? AppDelegate
appDelegateTemp?.window?.rootViewController = UIStoryboard(name: "Main", bundle: Bundle.main).instantiateInitialViewController()
}
MyTabTh...
Remove non-ascii character in string
...fo/unicode/char/200B/index.htm
https://en.wikipedia.org/wiki/Left-to-right_mark
Note that although the encoding of the embedded character is UTF-8, the encoding in the regular expression is not. Although the character is embedded in the string as three bytes (in my case) of UTF-8, the instructio...
Using arrays or std::vectors in C++, what's the performance gap?
...mbly code was generated by gcc 4.1.0 invoked with g++ -O3 -S on a
// x86_64-suse-linux machine.
#include <vector>
struct S
{
int padding;
std::vector<int> v;
int * p;
std::vector<int>::iterator i;
};
int pointer_index (S & s) { return s.p[3]; }
// movq 32(%r...
