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jsonify a SQLAlchemy result set in Flask [duplicate]
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It seems that you actually haven't executed your query. Try following:
return jsonify(json_list = qryresult.all())
[Edit]: Problem with jsonify is, that usually the objects cannot be jsonified automatically. Even Python's datetime fails ;)
Wha...
Remove all occurrences of a value from a list?
...on over the filter+lambda; the former is more readable in addition to generally more efficient.
– habnabit
Jul 21 '09 at 4:28
17
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__getattr__ on a module
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A while ago, Guido declared that all special method lookups on
new-style classes bypass __getattr__ and __getattribute__. Dunder methods had previously worked on modules - you could, for example, use a module as a context manager simply by defining __enter__...
What's the UIScrollView contentInset property for?
... answered Dec 31 '09 at 1:21
jballjball
23.1k88 gold badges6464 silver badges9191 bronze badges
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Performance difference for control structures 'for' and 'foreach' in C#
...t will depend on whether you're doing any real work in the loop. In almost all cases, the difference to performance won't be significant, but the difference to readability favours the foreach loop.
I'd personally use LINQ to avoid the "if" too:
foreach (var item in list.Where(condition))
{
}
EDI...
Does python have an equivalent to Java Class.forName()?
...takes a fully qualified class name and returns the class, however you have all the pieces needed to build that, and you can connect them together.
One bit of advice though: don't try to program in Java style when you're in python.
If you can explain what is it that you're trying to do, maybe we ca...
Difference between except: and except Exception as e: in Python
... print e.message, e.args
...
>>> catch()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "<stdin>", line 3, in catch
BaseException
Which a bare except does:
>>> def catch():
... try:
... raise BaseException()
... ...
Capturing Groups From a Grep RegEx
...egex="[0-9]+_([a-z]+)_[0-9a-z]*"
for f in $files # unquoted in order to allow the glob to expand
do
if [[ $f =~ $regex ]]
then
name="${BASH_REMATCH[1]}"
echo "${name}.jpg" # concatenate strings
name="${name}.jpg" # same thing stored in a variable
else
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What are the mechanics of short string optimization in libc++?
...ver, I would like to know in more detail how it works in practice, specifically in the libc++ implementation:
2 Answers
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Which method performs better: .Any() vs .Count() > 0?
...le<T> sequence.
For just IEnumerable<T>, then Any() will generally be quicker, as it only has to look at one iteration. However, note that the LINQ-to-Objects implementation of Count() does check for ICollection<T> (using .Count as an optimisation) - so if your underlying data-sou...