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How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...ons that might occur.
Cross-posting from another answer I gave yesterday (https://stackoverflow.com/a/44395983/2156909)
SQLAlchemy supports ON CONFLICT now with two methods on_conflict_do_update() and on_conflict_do_nothing():
Copying from the documentation:
from sqlalchemy.dialects.postgresql i...
design a stack such that getMinimum( ) should be O(1)
... public int getMin() {
return (int)min;
}
}
Credit goes to: https://leetcode.com/discuss/15679/share-my-java-solution-with-only-one-stack
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Python circular importing?
... this issue from Django, you should know that the docs provide a solution:
https://docs.djangoproject.com/en/1.10/ref/models/fields/#foreignkey
"...To refer to models defined in another application, you can explicitly specify a model with the full application label. For example, if the Manufacturer...
Make git automatically remove trailing whitespace before committing
... the tree is dirty
#
# The 'rebase --whitespace=fix' trick is from here:
# https://stackoverflow.com/a/19156679/470844
fixws = !"\
if (! git diff-files --quiet .) && \
(! git diff-index --quiet --cached HEAD) ; then \
git commit -m FIXWS_SAVE_INDEX && \
git stash save ...
Do HttpClient and HttpClientHandler have to be disposed between requests?
...r periodically or via some mechanism that learns about the DNS change. See https://github.com/dotnet/corefx/issues/11224 for more information (I suggest reading it carefully before blindly using the code suggested in the linked blog post).
...
Getting an element from a Set
... MagicSet, that makes the usage of an Map "transparent" to the developer.
https://github.com/ricpacca/magicset
Like the original Java HashSet, a MagicHashSet (which is one of the implementations of MagicSet provided in the library) uses a backing HashMap, but instead of having elements as keys a...
Multiple inheritance/prototypes in JavaScript
... inheritance.
my rather convoluted example of the above is available at https://github.com/cwolves/Fetch/blob/master/support/plugins/klass/klass.js
Note that there is some dead code in that file, but it allows multiple inheritance if you want to take a look.
If you want chained inheritance (N...
LINQ-to-SQL vs stored procedures? [closed]
...d with all sorts of different plans for the exact same query.
More here: https://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=363290
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Why use AJAX when WebSockets is available?
...rier quite easily via our home page, which you can access in both HTTP and HTTPS. It tries WebSockets and falls back to HTTP if they are blocked. Use this URL to display a widget in the middle that reports the current transport: lightstreamer.com/?s
– Alessandro Alinone
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When to use setAttribute vs .attribute= in JavaScript?
...deValue.
Performance
I've built a jsperf test case to show the difference: https://jsperf.com/set-attribute-comparison. Basically, In order:
Custom properties because they don't affect the DOM and are not attributes.
Special mappings provided by the browser (dir, id, className).
If attributes alrea...