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Why is iterating through a large Django QuerySet consuming massive amounts of memory?
...rst time you iterate over it. For example, this will print the headline of all entries in the database:
for e in Entry.objects.all():
print e.headline
So your ten million rows are retrieved, all at once, when you first enter that loop and get the iterating form of the queryset. The wait ...
How do I pass values to the constructor on my wcf service?
... How can I use it for self hosting? I receive an exception after calling to CreateServiceHost. I can only call to the protected method public override ServiceHostBase CreateServiceHost(string constructorString, Uri[] baseAddresses); The exception is The exception message was: 'ServiceHostF...
Is the LIKE operator case-sensitive with MSSQL Server?
...r that is case sensitive, it is the column itself.
When a SQL Server installation is performed a default collation is chosen to the instance. Unless explicitly mentioned otherwise (check the collate clause bellow) when a new database is created it inherits the collation from the instance and when ...
Where do the Python unit tests go?
...
For a file module.py, the unit test should normally be called test_module.py, following Pythonic naming conventions.
There are several commonly accepted places to put test_module.py:
In the same directory as module.py.
In ../tests/test_module.py (at the same level as t...
Proper way to handle multiple forms on one page in Django
...ta. Include some hidden inputs if your froms don't have unique fields with all possible values being not empty.
– Denis Otkidach
Oct 24 '09 at 16:39
14
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Get path of executable
...uriousguy: You'd want to do it if, for example, your program might get installed in a directory of the user's choosing. You need to be able to find your executable and its support files somehow.
– greyfade
Jun 25 '12 at 3:11
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Standardize data columns in R
I have a dataset called spam which contains 58 columns and approximately 3500 rows of data related to spam messages.
15 ...
apt-get for Cygwin?
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apt-cyg orks really well. Just installed rsync, openssh, mc and others.
– Jako
Feb 14 '13 at 0:51
9
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Perform debounce in React.js
...>
AwesomeDebouncePromise(searchFunction, 300)
);
// The async callback is run each time the text changes,
// but as the search function is debounced, it does not
// fire a new request on each keystroke
const searchResults = useAsync(
async () => {
if (inputText.length ...
Count number of records returned by group by
...his to DISTINCT COUNT() OVER(), and the query performance improved dramatically.
– Joe Aldrich
Sep 20 '17 at 13:33
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