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Is there a difference between “==” and “is”?
... a
True
In your case, the second test only works because Python caches small integer objects, which is an implementation detail. For larger integers, this does not work:
>>> 1000 is 10**3
False
>>> 1000 == 10**3
True
The same holds true for string literals:
>>> "a" i...
Rails 2.3-style plugins and deprecation warnings running task in Heroku
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Yep, I realize that all the warnings came from my Heroku scripts and logs. I'll assume that (a) it's the plugin injections and (b) that the Heroku team will fix this before it becomes an actual problem.
– fearless_fool
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Update MongoDB field using value of another field
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The best way to do this is in version 4.2+ which allows using of aggregation pipeline in the update document and the updateOne, updateMany or update collection method. Note that the latter has been deprecated in most if not all languages drivers.
MongoDB 4.2+
Version 4.2 ...
mongodb group values by multiple fields
... $slice just off the basic aggregation result. For "large" results, run parallel queries instead for each grouping ( a demonstration listing is at the end of the answer ), or wait for SERVER-9377 to resolve, which would allow a "limit" to the number of items to $push to an array.
db.books.aggregate(...
Pointers in Python?
...ur request is utterly impossible. Why ask for something impossible and totally different from the (possible) thing you actually want?!
Maybe you don't realize how drastically different barenames and decorated names are. When you refer to a barename a, you're getting exactly the object a was last ...
Removing Data From ElasticSearch
...lasticSearch. I have deleted my indexes. However, that doesn't seem to actually remove the data itself. The other stuff I've seen points to the Delete by Query feature. However, I'm not even sure what to query on. I know my indexes. Essentially, I'd like to figure out how to do a
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What is the difference between a field and a property?
...sed via get and set properties. Properties provide a level of abstraction allowing you to change the fields while not affecting the external way they are accessed by the things that use your class.
public class MyClass
{
// this is a field. It is private to your class and stores the actual da...
How do I expire a PHP session after 30 minutes?
...ms with filesystems where atime tracking is not available.
So it additionally might occur that a session data file is deleted while the session itself is still considered as valid because the session data was not updated recently.
And second:
session.cookie_lifetime
session.cookie_lifetime ...
What is a regular expression which will match a valid domain name without a subdomain?
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This should match all cases I think: ^([a-z0-9])(([a-z0-9-]{1,61})?[a-z0-9]{1})?(\.[a-z0-9](([a-z0-9-]{1,61})?[a-z0-9]{1})?)?(\.[a-zA-Z]{2,4})+$
– transilvlad
May 16 '13 at 16:38
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JavaScript open in a new window, not tab
I have a select box that calls window.open(url) when an item is selected. Firefox will open the page in a new tab by default. However, I would like the page to open in a new window, not a new tab.
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