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Does MongoDB's $in clause guarantee order
...the results
{ "$sort": { "weight": 1 } }
])
So that would be the expanded form. What basically happens here is that just as the array of values is passed to $in you also construct a "nested" $cond statement to test the values and assign an appropriate weight. As that "weight" value reflects t...
ERROR 1452: Cannot add or update a child row: a foreign key constraint fails
...relationships involve a parent table that holds the
central data values, and a child table with identical values pointing
back to its parent. The FOREIGN KEY clause is specified in the child
table.
It will reject any INSERT or UPDATE operation that attempts to create
a foreign key value...
What is the use for IHttpHandler.IsReusable?
I'm writing a IHttpHandler and I'll need to implement a IsReusable property. When I look at the MSDN documentation it says:
...
Why does the CheckBoxFor render an additional input tag, and how can I get the value using the FormC
...e a look here:
http://forums.asp.net/t/1314753.aspx
This isn't a bug, and is in fact the same approach that both Ruby on
Rails and MonoRail use.
When you submit a form with a checkbox, the value is only posted if
the checkbox is checked. So, if you leave the checkbox unchecked then
n...
What is the proper way to format a multi-line dict in Python?
...uld use a similar but not identical format as your format 3. Here is mine, and why.
my_dictionary = { # Don't think dict(...) notation has more readability
"key1": 1, # Indent by one press of TAB (i.e. 4 spaces)
"key2": 2, # Same indentation scale as above
"key3": 3, # Keep this final c...
Unnecessary curly braces in C++?
...ould not do this until C99. :)
Since C++ has destructors, it can also be handy to have resources (files, mutexes, whatever) automatically released as the scope exits, which can make things cleaner. This means you can hold on to some shared resource for a shorter duration than you would if you grabb...
How to convert all text to lowercase in Vim
...rocessor). If you want to convert text to lowercase, create a visual block and press u (or U to convert to uppercase). Tilde (~) in command mode reverses case of the character under the cursor.
If you want to see all text in Vim in small caps, you might want to look at the guifont option, or type :s...
Container View Controller Examples [closed]
...roller Class Reference . I feel I need a little more information than that and an example implementation would be nice. Google has turned up nothing at all.
...
What is the most efficient way of finding all the factors of a number in Python?
...
The reduce(list.__add__, ...) is taking the little lists of [fac1, fac2] and joining them together in one long list.
The [i, n/i] for i in range(1, int(sqrt(n)) + 1) if n % i == 0 returns a pair of factors if the remainder when you divide n by the smaller one is zero (it doesn't need to check the...
Sorting an array of objects by property values
I've got the following objects using AJAX and stored them in an array:
30 Answers
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