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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 ...
Where is shared_ptr?
...rking). Simply stating std , tr1 and <memory> is not helping at all! I have downloaded boosts and all but still it doesn't show up! Can someone help me by telling exactly where to find it?
...
Referencing system.management.automation.dll in Visual Studio
...g it updated, releasing new packages, etc.
– Ben Randall
Feb 5 '16 at 19:24
last updated 29/03/2013 " The owner has un...
How to find if a native DLL file is compiled as x64 or x86?
...
You can use DUMPBIN too. Use the /headers or /all flag and its the first file header listed.
dumpbin /headers cv210.dll
64-bit
Microsoft (R) COFF/PE Dumper Version 10.00.30319.01
Copyright (C) Microsoft Corporation. All rights reserved.
Dump of file cv210.dll
PE ...
How to avoid 'cannot read property of undefined' errors?
...
Catching all exceptions without re-throwing is bad, and generally using exceptions as part of the expected flow of execution is also not great -- even though in this case it's pretty well contained.
– hugo
...
How do I modify the URL without reloading the page?
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@CHiRiLo check out history.js which provides a fallback for browsers that don't support the HTML5 history API.
– David Murdoch
Sep 19 '12 at 22:21
25
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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 ...
What is the use of the @Temporal annotation in Hibernate?
...n the element collection value is of such a temporal type.
In plain Java APIs, the temporal precision of time is not defined. When dealing with temporal data, you might want to describe the expected precision in database. Temporal data can have DATE, TIME, or TIMESTAMP precision (i.e., the actual ...
Heroku NodeJS http to https ssl forced redirect
... to the accepted answer above, but:
Ensures you use "app.use" (for all actions, not just get)
Explicitly externalises the forceSsl logic into a declared function
Does not use '*' with "app.use" - this actually failed when I
tested it.
Here, I only want SSL in production. (Change as ...
How to handle floats and decimal separators with html5 input type number
... has a default value of 1. If you want the input's validation algorithm to allow floating-point values, specify a step accordingly.
For example, I wanted dollar amounts, so I specified a step like this:
<input type="number" name="price"
pattern="[0-9]+([\.,][0-9]+)?" step="0.01"
...