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mongodb: insert if not exists
... has built-in support for this. Pass an extra parameter to your update() call: {upsert:true}. For example:
key = {'key':'value'}
data = {'key2':'value2', 'key3':'value3'};
coll.update(key, data, upsert=True); #In python upsert must be passed as a keyword argument
This replaces your if-find-els...
Best XML Parser for PHP [duplicate]
...saves on memory. You pay for that with not being able to use XPath.
Personally, I find SimpleXml quite limiting (hence simple) in what it offers over DOM. You can switch between DOM and SimpleXml easily though, but I usually dont bother and go the DOM route directly. DOM is an implementation of the...
Django DB Settings 'Improperly Configured' Error
...--settings=mysite.settings (or whatever settings module you use)
Set DJANGO_SETTINGS_MODULE environment variable in your OS to mysite.settings
(This is removed in Django 1.6) Use setup_environ in the python interpreter:
from django.core.management import setup_environ
from mysite import settings
s...
How to make ng-repeat filter out duplicate results
...sion of ui utils, you can just include ui.unique on its own. use bower install just for the module.
– Learning stats by example
Feb 11 '15 at 19:59
...
map vs. hash_map in C++
...tied to that key.
map is implemented as a balanced binary search tree (usually a red/black tree).
An unordered_map should give slightly better performance for accessing known elements of the collection, but a map will have additional useful characteristics (e.g. it is stored in sorted order, which...
Convert unix time to readable date in pandas dataframe
...12.15
3 1349979305 12.19
4 1350065705 12.15
In [25]: df['date'] = pd.to_datetime(df['date'],unit='s')
In [26]: df.head()
Out[26]:
date price
0 2012-10-08 18:15:05 12.08
1 2012-10-09 18:15:05 12.35
2 2012-10-10 18:15:05 12.15
3 2012-10-11 18:15:05 12.19
4 2012-10-12 18:15:...
Match whitespace but not newlines
...ghteen horizontal ones which match \h. \s matches twenty-three characters
All whitespace characters are either vertical or horizontal with no overlap, but they are not proper subsets because \h also matches U+00A0 NO-BREAK SPACE, and \v also matches U+0085 NEXT LINE, neither of which are matched by...
What Makes a Good Unit Test? [closed]
...ng lots of automated tests and that you also have run into some common pitfalls when unit testing.
18 Answers
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Why would finding a type's initializer throw a NullReferenceException?
....cs:
(196c.1874): Access violation - code c0000005 (first chance)
mscorlib_ni!System.RuntimeType.GetConstructorImpl(System.Reflection.BindingFlags, System.Reflection.Binder, System.Reflection.CallingConventions, System.Type[], System.Reflection.ParameterModifier[])+0xa3:
000007fe`e5735403 488b4608 ...
std::unique_ptr with an incomplete type won't compile
...
I find your first solution (adding the foo destructor) allows the class declaration itself to compile, but declaring an object of that type anywhere results in the original error ("invalid application of 'sizeof'...").
– Jeff Trull
Sep 30 '1...