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How to pass a user defined argument in scrapy spider
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The above code is only partially working for me. For eg. If I define domain using self.domain, I'm still not able to access it outside the __init__ method. Python throws a not defined error. BTW, why have you omitted the super call? PS. I'm working wit...
How can I get list of values from dict?
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How does setting baselineAligned to false improve performance in LinearLayout?
...="false" , you're preventing the extra work your app's layout has to do in order to Align its children's baselines; which can obviously increase the performance. (Fewer unnecessary operations on UI => Better performance)
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Getting the docstring from a function
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On ipython or jupyter notebook, you can use all the above mentioned ways, but i go with
my_func?
or
?my_func
for quick summary of both method signature and docstring.
I avoid using
my_func??
(as commented by @rohan) for docstring and use it only to check th...
The multi-part identifier could not be bound
...GROUP BY maxa
) AS dkcd ON dkcd.maxa = a.maxa
WHERE a.maxa <> '99'
ORDER BY a.maxa
Here the tables a and b are joined first, then the result is joined to dkcd. Basically, this is the same query as yours, only using a different syntax for one of the joins, which makes a great difference: th...
Making a property deserialize but not serialize with json.net
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There are actually several fairly simple approaches you can use to achieve the result you want.
Let's assume, for example, that you have your classes currently defined like this:
class Config
{
public Fizz ObsoleteSetting { get; set;...
In MySQL queries, why use join instead of where?
...x queries can benefit from using ANSI-92 syntax:
Ability to control JOIN order - the order which tables are scanned
Ability to apply filter criteria on a table prior to joining
From a Maintenance Perspective:
There are numerous reasons to use ANSI-92 JOIN syntax over ANSI-89:
More readable...
Iterating over dictionaries using 'for' loops
... Might make sense to mention that items will be iterated in unpredictable order and sorted is needed to stabilize it.
– yugr
Aug 25 '18 at 9:06
6
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How does an underscore in front of a variable in a cocoa objective-c class work?
...to-generated accessor (for the property) knows which ivar to use. Specifically, in your implementation file, your synthesize should look like this:
@synthesize missionName = _missionName;
More generically, this is:
@synthesize propertyName = _ivarName;
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How do I preview emails in Rails?
...tes contain any dynamic data, it won't work. E.g. suppose your email is an order receipt and within it you print out @order.total_price - using the previous method the @order variable will be nil.
Here's a little recipe I use:
First, since this email preview functionality is definitely for interna...