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Generating a UUID in Postgres for Insert statement?
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edited Jan 27 '17 at 11:35
rightfold
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JPA eager fetch does not join
...d mapped entity/collection of all root entities retrieved in first query = 2 queries
JOIN => one query to fetch both root entities and all of their mapped entity/collection = 1 query
So SELECT and JOIN are two extremes and SUBSELECT falls in between. One can choose suitable strategy based on he...
JavaScript % (modulo) gives a negative result for negative numbers
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273
Number.prototype.mod = function(n) {
return ((this%n)+n)%n;
};
Taken from this article: ...
NSInvocation for Dummies?
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284
According to Apple's NSInvocation class reference:
An NSInvocation is an Objective-C messa...
Using “like” wildcard in prepared statement
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282
You need to set it in the value itself, not in the prepared statement SQL string.
So, this s...
iOS: Compare two dates
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210
According to Apple documentation of NSDate compare:
Returns an NSComparisonResult value th...
How to export table as CSV with headings on Postgresql?
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12 Answers
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Delete a key from a MongoDB document using Mongoose
...collection.update({_id: user._id}, {$unset: {field: 1 }});
Since version 2.0 you can do:
User.update({_id: user._id}, {$unset: {field: 1 }}, callback);
And since version 2.4, if you have an instance of a model already you can do:
doc.field = undefined;
doc.save(callback);
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Is there a way to detach matplotlib plots so that the computation can continue?
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221
Use matplotlib's calls that won't block:
Using draw():
from matplotlib.pyplot import plot, dra...
can we use xpath with BeautifulSoup?
...you can use the .xpath() method to search for elements.
try:
# Python 2
from urllib2 import urlopen
except ImportError:
from urllib.request import urlopen
from lxml import etree
url = "http://www.example.com/servlet/av/ResultTemplate=AVResult.html"
response = urlopen(url)
htmlparser =...