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What are the uses for Cross Join?
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If you have a "grid" that you want to populate completely, like size and color information for a particular article of clothing:
select
size,
color
from
sizes CROSS JOIN colors
Maybe you want a table that contains a row for every minute in the day, and you want to use it to ver...
Use of 'const' for function parameters
... you just make functions const when necessary or do you go the whole hog and use it everywhere? For example, imagine a simple mutator that takes a single boolean parameter:
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How to tell Xcode where my info.plist and .pch files are
I renamed my project and it's files and now Xcode is still looking for the old info.plist file. Where do I set the locations of the .plist and .pch files that it needs.
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Codesign error: Certificate identity appearing twice
...had the same problem.
It has been fixed.
It came after I submitted an app and installed a few certificates to sign the app.
Quick Fix:
Open up KEYCHAIN ACCESS > click on MY CERTIFICATES> in there you will probably see
iPhone Developer: . You will probably see it TWICE!
Select the one with ...
Difference between Covariance & Contra-variance
I am having trouble understanding the difference between covariance and contravariance.
5 Answers
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Good PHP ORM Library?
...ates everything on the fly)
No models
etc.
It even does all the locking and transactions for you and monitors performance in the background. (Heck! it even does garbage collection....) Best of all... you don't have to write a single... line of code... Jesus this, ORM layer, saved me ass!
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Convert PEM to PPK file format
...EM files to PPK files? (you may guess that Amazon EC2 gives me a PEM file, and I need to use the PPK format for SSH connectivity).
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Meaning of @classmethod and @staticmethod for beginner? [duplicate]
Could someone explain to me the meaning of @classmethod and @staticmethod in python? I need to know the difference and the meaning.
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UITableView : viewForHeaderInSection: not called during reloadData:
I've set up the tableview with correct delegate and datasource linkages.. the reloadData method calls the datasource and the delegate methods except for viewForHeaderInSection: .
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Naming convention - underscore in C++ and C# variables
..., its use is always somewhat different to each person. Here's how I understand them for the two languages in question:
In C++, an underscore usually indicates a private member variable.
In C#, I usually see it used only when defining the underlying private member variable for a public property. Ot...