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MySQL Cannot Add Foreign Key Constraint
...ing to add Foreign Key constraints to my database as a project requirement and it worked the first time or two on different tables, but I have two tables on which I get an error when trying to add the Foreign Key Constraints.
The error message that I get is:
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difference between throw and throw new Exception()
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throw; rethrows the original exception and preserves its original stack trace.
throw ex; throws the original exception but resets the stack trace, destroying all stack trace information until your catch block.
NEVER write throw ex;
throw new Exception(ex.Message...
What does the ng stand for in Angular.js directives
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The prefix ng stands for "Angular;" all of the built-in directives that ship with Angular use that prefix. Similarly, it is recommended that you do not use the ng prefix on your own directives in order to avoid possible name collisions in fu...
Why is std::map implemented as a red-black tree?
...bly the two most common self balancing tree algorithms are Red-Black trees and AVL trees. To balance the tree after an insertion/update both algorithms use the notion of rotations where the nodes of the tree are rotated to perform the re-balancing.
While in both algorithms the insert/delete operat...
How much does it cost to develop an iPhone application? [closed]
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I'm one of the developers for Twitterrific and to be honest, I can't tell you how many hours have gone into the product. I can tell you everyone who upvoted the estimate of 160 hours for development and 40 hours for design is fricken' high. (I'd use another phrase, bu...
PostgreSQL error 'Could not connect to server: No such file or directory'
...n your postgres directory, probably /usr/local/var/postgres/
remove this and start server.
Check - https://github.com/mperham/lunchy is a great wrapper for launchctl.
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How to overload std::swap()
std::swap() is used by many std containers (such as std::list and std::vector ) during sorting and even assignment.
4 A...
Understanding Spliterator, Collector and Stream in Java 8
I am having trouble understanding the Stream interface in Java 8, especially where it has to do with the Spliterator and Collector interfaces. My problem is that I simply can't understand Spliterator and the Collector interfaces yet, and as a result, the Stream interface is still somewha...
How do I clear the terminal screen in Haskell?
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:! run the shell command
:! cls under windows
:! clear under linux and OS X
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What's the right way to pass form element state to sibling/parent elements?
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So, if I'm understanding you correctly, your first solution is suggesting that you're keeping state in your root component? I can't speak for the creators of React, but generally, I find this to be a proper solution.
Maintaining state is one...