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How can I temporarily disable a foreign key constraint in MySQL?
... answered Mar 19 '13 at 14:07
Andrew CampbellAndrew Campbell
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Introducing FOREIGN KEY constraint may cause cycles or multiple cascade paths - why?
I've been wrestling with this for a while and can't quite figure out what's happening. I have a Card entity which contains Sides (usually 2) - and both Cards and Sides have a Stage. I'm using EF Codefirst migrations and the migrations are failing with this error:
...
enum - getting value of enum on string conversion
...at:
print(D.x.value)
See the Programmatic access to enumeration members and their attributes section:
If you have an enum member and need its name or value:
>>>
>>> member = Color.red
>>> member.name
'red'
>>> member.value
1
You could add a __str__ meth...
What does JVM flag CMSClassUnloadingEnabled actually do?
...//blogs.oracle.com/poonam/about-g1-garbage-collector,-permanent-generation-and-metaspace Kudos go to mt.uulu
For Java 5-7:
The standard Oracle/Sun VM look on the world is: Classes are forever. So once loaded, they stay in memory even if no one cares anymore. This usually is no problem since you do...
What is the rationale for all comparisons returning false for IEEE754 NaN values?
...ify things a bit.
First off, floating-point numbers are not real numbers, and floating-point arithmetic does not satisfy the axioms of real arithmetic. Trichotomy is not the only property of real arithmetic that does not hold for floats, nor even the most important. For example:
Addition is not...
What does mysql error 1025 (HY000): Error on rename of './foo' (errorno: 150) mean?
...se the InnoDB engine. In that case you would have to drop the foreign key, and then do the alter table and drop the column.
But the tricky part is that you can't drop the foreign key using the column name, but instead you would have to find the name used to index it. To find that, issue the followi...
How to append something to an array?
...to the length property. The interpreter does an amazing job at that itself and it will not make any difference in The Real World whether you optimize it away or not. If your array becomes so huge that optimizing .length would actually help, most probably an array is not the right data structure anym...
When should I use Debug.Assert()?
...graduated with a CS degree. I've known about assertions for a while in C++ and C, but had no idea they existed in C# and .NET at all until recently.
...
What does “atomic” mean in programming?
... written using two separate operations: one that writes the first 32 bits, and a second one which writes the last 32 bits. That means that another thread might read the value of foo, and see the intermediate state.
Making the operation atomic consists in using synchronization mechanisms in order t...
How to 'grep' a continuous stream?
...
@MichaelNiemand you could use tail -F file | grep --line-buffered my_pattern
– jcfrei
May 26 '15 at 16:28
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