大约有 30,000 项符合查询结果（耗时：0.0423秒） [XML]
MongoDB atomic “findOrCreate”: findOne, insert if nonexistent, but do not update
...y happen when inserting documents.
This, combined with the upsert option, means you can use findAndModify to achieve an atomic findOrCreate-like operation.
db.collection.findAndModify({
query: { _id: "some potentially existing id" },
update: {
$setOnInsert: { foo: "bar" }
},
new: true,...
How to leave a message for a github.com user
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What is the user has no activity? I mean, simply created an account and never logged in again?
– Hossein
Jul 12 '14 at 21:03
6
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How to pass values between Fragments
... clicked the data is sent. When it is sent it replaces the fragment. Which means the list gets renewed every time. Therefore, not keeping the list of items in memory.
– wesley franks
Jun 29 '19 at 20:43
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How to avoid reverse engineering of an APK file?
...Charlie four times and John four times. On the server, interpret what they mean and add it up. This prevents a hacker from sending arbitrary values to your server, as they do not know what word corresponds to what value. As an added measure of security, you could have an equation similar to point 3 ...
Using NumberPicker Widget with Strings
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String value = String.valueOf(picker.getValue());
You could mean something else, but it isn't very clear what you mean.
UPDATED:
You can fake it by setting your own formatter:
CountryFormatter implements Formatter {
public String toString(int value) {
switch(value) {
...
XPath query to get nth instance of an element
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This is a FAQ:
//somexpression[$N]
means "Find every node selected by //somexpression that is the $Nth child of its parent".
What you want is:
(//input[@id="search_query"])[2]
Remember: The [] operator has higher precedence (priority) than the // abbrevia...
How can you dynamically create variables via a while loop? [duplicate]
...bles dynamically via a while loop in Python. Does anyone have any creative means of doing this?
8 Answers
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How to convert int[] to Integer[] in Java?
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That's meanwhile the correct way. If you need the Integer-Array as a list you could write: List<Integer> list = IntStream.of(q).boxed().collect(Collectors.toList());
– aw-think
Feb 27 '15...
NSURLRequest setting the HTTP header
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What does setValue:@"application/x-www-form-urlencoded" mean, is it sth custom?
– Dilara Albayrak
Mar 7 '16 at 13:28
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What does a script-Tag with src AND content mean?
...ingoftruth's question: html is editable by clients, so run it through eval means giving the user the ability to run arbitrary code, which is a massive security vulnerability.
– Federico S
Sep 21 at 20:05
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