大约有 40,000 项符合查询结果（耗时：0.0605秒） [XML]
Find document with array that contains a specific value
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@AeroWang use this db.person.find( { favouriteFoods: { $all: ["sushi", "sashimi"] } } ) will return all person loving both "sushi" and "sashimi" someone pointed it a few answers below
– benraay
Jul 1 at 14:20
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Create a string of variable length, filled with a repeated character
...slower than a string-concatenation-based implementation. It performs especially badly on large strings. See below for full performance details.
On Firefox, Chrome, Node.js MacOS, Node.js Ubuntu, and Safari, the fastest implementation I tested was:
function repeatChar(count, ch) {
if (count == ...
continue processing php after sending http response
My script is called by server. From server I'll receive ID_OF_MESSAGE and TEXT_OF_MESSAGE .
12 Answers
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Difference between author and committer in Git?
...ld find was using the environment variables to override the committer:
GIT_COMMITTER_NAME='a' GIT_COMMITTER_EMAIL='a' git commit --author 'a <a>'
How to get the committer and commit date of a given commit?
Only author data shows by default on git log.
To see the committer date you can eit...
Adding gif image in an ImageView in android
...imationActivity: -
public class AnimationActivity extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
InputStream stream = null;
try {
stream = getAssets().open("pig...
What does “export” do in shell programming? [duplicate]
... '^variable='
$ # No environment variable called variable
$ variable=Hello # Create local (non-exported) variable with value
$ env | grep '^variable='
$ # Still no environment variable called variable
$ export variable ...
If my interface must return Task what is the best way to have a no-operation implementation?
...mprove performance even more if you cache the already completed task since all instances of completed tasks are the same:
public static class TaskExtensions
{
public static readonly Task CompletedTask = Task.FromResult(false);
}
With TaskExtensions.CompletedTask you can use the same instance ...
Regular vs Context Free Grammars
...ammar is either right or left linear, whereas context free grammar is basically any combination of terminals and non-terminals. Hence you can see that regular grammar is a subset of context-free grammar.
So for a palindrome for instance, is of the form,
S->ABA
A->something
B->something
...
Google Sheets API Setup · App Inventor 2 中文网
...le you got from the Service Account setup steps.
Unable to parse range: ______
If you get this error message, there may be an error with the range that you
provided. This could mean that the sheetName you’ve provided does not actually
exist, or that the reference you provided is not valid A1-...
Swift make method parameter mutable?
...eclare an inout parameter. Think: passing in a pointer.
func reduceToZero(_ x: inout Int) {
while (x != 0) {
x = x-1
}
}
var a = 3
reduceToZero(&a)
print(a) // will print '0'
This can be particularly useful in recursion.
Apple's inout declaration guidelines can be found...