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What is the difference between an abstract function and a virtual function?
What is the difference between an abstract function and a virtual function? In which cases is it recommended to use virtual or abstract? Which one is the best approach?
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MySQL Error 1215: Cannot add foreign key constraint
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I'm guessing that Clients.Case_Number and/or Staff.Emp_ID are not exactly the same data type as Clients_has_Staff.Clients_Case_Number and Clients_has_Staff.Staff_Emp_ID.
Perhaps the columns in the parent tables are INT UNSIGNED?
They need to be exactly the same...
Efficient way to return a std::vector in c++
How much data is copied, when returning a std::vector in a function and how big an optimization will it be to place the std::vector in free-store (on the heap) and return a pointer instead i.e. is:
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What is the difference between the GNU Makefile variable assignments =, ?=, := and +=?
... but any other variables mentioned with the value field are recursively expanded with their value at the point at which the variable is used, not the one it had when it was declared
Immediate Set
VARIABLE := value
Setting of a variable with simple expansion of the values inside - values within i...
JavaScript DOM remove element
I'm trying to test if a DOM element exists, and if it does exist delete it, and if it doesn't exist create it.
5 Answers
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A route named “x” is already in the route collection. Route names must be unique. Exception with ASP
I'm doing an ASP.NET MVC 3 web service and I keep getting this exception intermittently.
14 Answers
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Centering a view in its superview using Visual Format Language
I just started learning AutoLayout for iOS and had a look at Visual Format Language.
14 Answers
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How to get CRON to call in the correct PATHs
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I used /etc/crontab. I used vi and entered in the PATHs I needed into this file and ran it as root. The normal crontab overwrites PATHs that you have set up. A good tutorial on how to do this.
The systemwide cron file looks like this:
This has the userna...
Java ArrayList copy
... l1 of size 10. I assign l1 to new list reference type l2 . Will l1 and l2 point to same ArrayList object? Or is a copy of the ArrayList object assigned to l2 ?
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How can I parse a time string containing milliseconds in it with python?
... Thanks docs.python.org/library/datetime.html : New in version 2.6: time and datetime objects support a %f format code which expands to the number of microseconds in the object, zero-padded on the left to six places.
– ilkinulas
Mar 30 '09 at 18:01
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