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Why is iterating through a large Django QuerySet consuming massive amounts of memory?
...etching large items from database.
import gc
# Get the events in reverse order
eids = Event.objects.order_by("-id").values_list("id", flat=True)
for index, eid in enumerate(eids):
event = Event.object.get(id=eid)
# do necessary work with event
if index % 100 == 0:
gc.collect()
...
Android Min SDK Version vs. Target SDK Version
...e not required for the target version (which may otherwise be turned on in order to maintain forward-compatibility) or enable newer features that are not available to older applications. This does not mean that you can program different features for different versions of the platform—it simply inf...
How do I deserialize a JSON string into an NSDictionary? (For iOS 5+)
...version:) can be used in conjunction with JSONDecoder's decode(_:from:) in order to deserialize a JSON string into a dictionary.
Furthermore, with Swift 3 and Swift 4, String's data(using:allowLossyConversion:) can also be used in conjunction with JSONSerialization's jsonObject(with:options:...
Sort NSArray of date strings or objects
...s @selector(compare:) as the parameter. The -[NSDate compare:] method will order dates in ascending order for you. This is simpler than creating an NSSortDescriptor, and much simpler than writing your own comparison function. (NSDate objects know how to compare themselves to each other at least as e...
What and where are the stack and heap?
...ion is called. The stack is always reserved in a LIFO (last in first out) order; the most recently reserved block is always the next block to be freed. This makes it really simple to keep track of the stack; freeing a block from the stack is nothing more than adjusting one pointer.
The heap is me...
Why should I use IHttpActionResult instead of HttpResponseMessage?
... Under the covers, this is how ActionFilters are implemented however, the ordering of those ActionFilters is not obvious when reading the action method which is one reason I'm not a fan of action filters.
However, by creating an IHttpActionResult that can be explicitly chained in your action metho...
How can I iterate over files in a given directory?
...e rules used by the Unix shell, although results are returned in arbitrary order. No tilde expansion is done, but *, ?, and character ranges expressed with [] will be correctly matched.
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Injecting Mockito mocks into a Spring bean
...
As of spring 3.2, the order of the beans no longer matters. See the section entitled "Generic Factory Methods" in this blog post: spring.io/blog/2012/11/07/…
– Ryan Walls
Oct 18 '13 at 15:59
...
Instance variables vs. class variables in Python
...ut how this works yet. It is very similar to variable access -- the search order of which is:
locals
nonlocals
globals
built-ins
For attribute access, the order is:
instance
class
base classes as determined by the MRO (method resolution order)
Both techniques work in an "inside-out" manner, ...
CSS selector for a checked radio button's label
...stify-content: center;
}
.filter-label {
display: inline-block;
border: 4px solid green;
padding: 10px 20px;
font-size: 1.4em;
text-align: center;
cursor: pointer;
}
main {
clear: left;
}
.content {
padding: 3% 10%;
display: none;
}
h1 {
font-size: 2em;
...