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What is the difference between inversedBy and mappedBy?
...at doctrine can now safely use JOIN SQL statements instead of two separate SELECT statements. Without mappedBy, the doctrine engine would not know from the JOIN statement it will create what variable in the class 'Task' to put the category information.
Hope this explains it a bit better.
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Switch statement fallthrough in C#?
...# had not yet added any "soft" keywords (like 'yield', 'var', 'from', and 'select'), so they had three real options: 1) make 'fallthrough' a hard keyword (you cant use it as a variable name), 2) write code necessary to support such an soft keyword, 3) use already reserved keywords. #1 was a big issu...
How to replace NaN values by Zeroes in a column of a Pandas Dataframe?
...360 -0.229738
4 0.000000 0.000000
To fill the NaNs in only one column, select just that column. in this case I'm using inplace=True to actually change the contents of df.
In [12]: df[1].fillna(0, inplace=True)
Out[12]:
0 0.000000
1 0.570994
2 0.000000
3 -0.229738
4 0.000000
Name...
Batch script: how to check for admin rights
... after clicking on a start menu icon, then right click on the shortcut and select "Run As Administrator".
echo ##########################################################
echo.
PAUSE
EXIT /B 1
)
@echo ON
Works on WinXP --> Win8 (including 32/64 bit versions).
EDIT: 8/28/2012 Updated...
REST API Best practices: args in query string vs in request body
...
Selecting how to structure your API based on development convenience is not a good practice.
– Eric Stein
Aug 19 '14 at 14:42
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What are some uses of decltype(auto)?
...
For non-generic code, like the initial example you gave, you can manually select to get a reference as a return type:
auto const& Example(int const& i)
{
return i;
}
but in generic code you want to be able to perfectly forward a return type without knowing whether you are dealing ...
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...
Which one will execute faster, if (flag==0) or if (0==flag)?
...is a user-defined type. Then it depends on which overload of operator== is selected. Of course it can seem stupid that they would not be symmetric, but it's certainly allowed, and I have seen other abuses already.
If flag is a built-in, then both should take the same speed.
From the Wikipedia arti...
Is it worth hashing passwords on the client side
... that such a replay attack cannot work, usually, by allowing the client to select a bunch of random bits, which are hashed along with the password, and also submitted in the clear to the server.
On the server:
generate a few bits of random
send these bits (in clear text) to the client
On the c...
Sorting an IList in C#
...rty, I believe you could sort as follows:
from c in list
orderby c.Engine
select c;
Edit: You do need to be quick to get answers in here. As I presented a slightly different syntax to the other answers, I will leave my answer - however, the other answers presented are equally valid.
...