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Create Django model or update if exists
...large collection it won't scale well. update_or_create always first runs a SELECT and thereafter an UPDATE.
for the_bar in bars:
updated_rows = SomeModel.objects.filter(bar=the_bar).update(foo=100)
if not updated_rows:
# if not exists, create new
SomeModel.object...
Best practices for SQL varchar column length [closed]
...hen you need to worry about it and make them smaller. But if you only ever select 1 row from that table, then you can just make them all 255 and it won't matter.
See: What are the optimum varchar sizes for MySQL?
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Does Python support multithreading? Can it speed up execution time?
...ross multiple cores. This extends to I/O controlled by the kernel, such as select() calls for socket reads and writes, making Python handle network events reasonably efficiently in a multi-threaded multi-core setup.
What many server deployments then do, is run more than one Python process, to let t...
How can you find the unused NuGet packages in a solution?
...n also project > Optimize Used References . . .
A window will pop up. Select all references and remove them all. Then go back and re-add the ones that give you a compiler error.
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Android EditText delete(backspace) key event
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Works as long you don't use selection (autocompletion)
– Javatar
Oct 17 '17 at 8:57
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How can I see all the issues I'm watching on Github?
...m any page by clicking the notification/bell icon on the top left and then selecting "Managed Notification" > "Subscriptions" from the left menu panel.
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Getting rid of all the rounded corners in Twitter Bootstrap
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This solution doesn't work for bootstrap styled <select> inputs. Probably due to the use of -webkit-appearance: menulist.
– johnsorrentino
Jul 16 '15 at 18:36
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Edit the root commit in Git?
...t
Then the root commit will show up in the rebase TODO list, and you can select to edit or reword it:
reword <root commit sha> <original message>
pick <other commit sha> <message>
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This is the explanation of --root from the Git rebase docs (emphasis mine):
Rebase ...
What is the difference between UTF-8 and Unicode?
...r wants to use. Also, when a text editor program reads a file, it needs to select a text encoding scheme to decode it correctly. Same goes when you are typing and entering a letter, the text editor needs to know what scheme you use so that it will save it correctly.
– Cheng
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获取文件系统映像及恢复删除的数据（FAT文件系统格式描述） - C/C++ - 清泛...
...str()<< L"/n";
}
int driveIndex;
std::cin >> driveIndex;//selecting a disk
std::vector<unsigned char> buffer;
//creating a path
std::wstring dumpPath(L"////.//PhysicalDrive");
wchar_t index[MAX_PATH];
_itow(devices.at(driveIndex).vHarddiskIndexes[0], index , MAX_P...