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Which rows are returned when using LIMIT with OFFSET in MySQL?
...
It will return 18 results starting on record #9 and finishing on record #26.
Start by reading the query from offset. First you offset by 8, which means you skip the first 8 results of the query. Then you limit by 18. Which means you consider records 9, 10, 11, 12, 13, 14,...
jsonify a SQLAlchemy result set in Flask [duplicate]
...y.
"""
return [ item.serialize for item in self.many2many]
And now for views I can just do:
return jsonify(json_list=[i.serialize for i in qryresult.all()])
Hope this helps ;)
[Edit 2019]:
In case you have more complex objects or circular references, use a library like marshmallo...
Forced naming of parameters in Python
... Parameters after “*” or “*identifier” are keyword-only parameters and
may only be passed used keyword arguments.
>>> def foo(pos, *, forcenamed):
... print(pos, forcenamed)
...
>>> foo(pos=10, forcenamed=20)
10 20
>>> foo(10, forcenamed=20)
10 20
>>&g...
pip broke. how to fix DistributionNotFound error?
...he reason is because as @Stephan said, I use easy_install to install pip, and the mixture of both py package manage tools led to the pkg_resources.DistributionNotFound problem.
The resolve is:
easy_install --upgrade pip
Remember: just use one of the above tools to manage your Py packages.
...
Why return NotImplemented instead of raising NotImplementedError
...
It's because __lt__() and related comparison methods are quite commonly used indirectly in list sorts and such. Sometimes the algorithm will choose to try another way or pick a default winner. Raising an exception would break out of the sort unles...
Timer function to provide time in nano seconds using C++
...ed about running the function repeatedly in a loop is correct.
For Linux (and BSD) you want to use clock_gettime().
#include <sys/time.h>
int main()
{
timespec ts;
// clock_gettime(CLOCK_MONOTONIC, &ts); // Works on FreeBSD
clock_gettime(CLOCK_REALTIME, &ts); // Works on Li...
C# operator overload for `+=`?
... think this is because there will be an effect for the Garbage collection and memory management, which is a potential security hole in CLR strong typed world.
Nevertheless, let's see what exactly an operator is. According to the famous Jeffrey Richter's book, each programming language has its own ...
Batch File; List files in directory, only filenames?
...t I'm having trouble with it. Basically, I am trying to write a Batch File and I need it to list all the files in a certain directory. The dir command will do this, but it also gives a bunch of other information; I want it to list ONLY the file names and exclude anything else.
...
Retain cycle on `self` with blocks
...'s no real alternative here. If you're designing your own block-based API, and it makes sense to do so, you could have the block get passed the value of self in as an argument. Unfortunately, this doesn't make sense for most APIs.
Please note that referencing an ivar has the exact same issue. If yo...
Does MongoDB's $in clause guarantee order
...the results
{ "$sort": { "weight": 1 } }
])
So that would be the expanded form. What basically happens here is that just as the array of values is passed to $in you also construct a "nested" $cond statement to test the values and assign an appropriate weight. As that "weight" value reflects t...