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Django Rest Framework File Upload
... very helpful thank you a lot. But i don't understand, why you are converting dict data to QueryDict in parser? In my case in Django, normal dictionary data work perfectly without converting.
– Metehan Gülaç
Apr 12 at 20:15
...
Add column to SQL Server
... use the ALTER TABLE... syntax.
Example
ALTER TABLE YourTable
ADD Foo INT NULL /*Adds a new int column existing rows will be
given a NULL value for the new column*/
Or
ALTER TABLE YourTable
ADD Bar INT NOT NULL DEFAULT(0) /*Adds a new int column existing rows will
...
What are the options for storing hierarchical data in a relational database? [closed]
... thought I'd give Celko a bit of competition by coming up with a method to convert an Adjacency List to Nested sets at speeds that just seem impossible. Here's the performance of the push stack method on my i5 laptop.
Duration for 1,000 Nodes = 00:00:00:870
Duration for 10,000 Nodes = 00:01...
What are the differences between the BLOB and TEXT datatypes in MySQL?
...
TEXT and CHAR will convert to/from the character set they have associated with time. BLOB and BINARY simply store bytes.
BLOB is used for storing binary data while Text is used to store large string.
BLOB values are treated as binary strings ...
What exactly is a reentrant function?
...
{
foo(nullptr);
}
At first sight, everything seems ok… But wait:
int main()
{
foo(bar);
return 0;
}
If the lock on mutex is not recursive, then here's what will happen, in the main thread:
main will call foo.
foo will acquire the lock.
foo will call bar, which will call foo.
th...
How to change current Theme at runtime in Android [duplicate]
...like this:
TaskStackBuilder.create(getActivity())
.addNextIntent(new Intent(getActivity(), MainActivity.class))
.addNextIntent(getActivity().getIntent())
.startActivities();
EDIT:
Just put the code above after you perform changing of theme on the UI or som...
Iterating C++ vector from the end to the beginning
...ere especially designed for that purpose. (And yes, incrementing a reverse_interator moves it backward.)
Now, in theory, your method (using begin()/end() & --i) would work, std::vector's iterator being bidirectional, but remember, end() isn't the last element — it's one beyond the last elemen...
Do you have to put Task.Run in a method to make it async?
...o the calling thread before it starts. In an async method, those "yield" points are await expressions.
This is very different than the term "asynchronous", as (mis)used by the MSDN documentation for years to mean "executes on a background thread".
To futher confuse the issue, async is very differe...
Media Queries: How to target desktop, tablet, and mobile?
...1281px) { /* hi-res laptops and desktops */ }
In practice, many designers convert pixels to ems, largely because ems afford better zooming. At standard zoom 1em === 16px, multiply pixels by 1em/16px to get ems. For example, 320px === 20em.
In response to the comment, min-width is standard in "mobil...
When to make a type non-movable in C++11?
...s address is part of its value. For example, the OS might keep a list of pointers to all initialized mutex objects. If std::mutex contained a native OS mutex type as a data member and the native type's address must stay fixed (because the OS maintains a list of pointers to its mutexes) then either s...