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JPA: How to have one-to-many relation of the same Entity type
...em.persist(daughter);
em.getTransaction().commit();
}
In this case, all three entity instances must be persisted before transaction commit. If I fail to persist one of the entities in the graph of parent-child relationships, then an exception is thrown on commit(). On Eclipselink, this is a...
How do I open an old MVC project in Visual Studio 2012 or Visual Studio 2013?
...unsupported MVC project in Visual Studio 2012 or Visual Studio 2013 is actually pretty easy to accomplish with two steps. In fact, as bytebender’s comment indicates, these same steps should apply to and work for MVC 1 projects. However, I haven’t tested them and therefore cannot guarantee that t...
Determining if an Object is of primitive type
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The types in an Object[] will never really be primitive - because you've got references! Here the type of i is int whereas the type of the object referenced by o is Integer (due to auto-boxing).
It sounds like you need to find out whether the type is a "wrapper ...
What are the “must have” jQuery plugins? [closed]
...hat have not already been described in other posts, I'll try and roll them all into a summarizing post.
– Dónal
Nov 6 '08 at 5:12
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Why isn't vector a STL container?
... avoid vector <bool> as it's not an STL container and it doesn't really hold bool s.
6 Answers
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How to create materialized views in SQL Server?
I am going to design a DW and I heard about materialized views. Actually I want to create a view and it should update automatically when base tables are changed. Can anyone explain with an query example..
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When should I use a List vs a LinkedList
... in list)
sum += item.A;
Even if you only access data essentially it is much slower!! I say never use a linkedList.
Here is another comparison performing a lot of inserts (we plan on inserting an item at the middle of the list)
Linked List (51 seconds)
LinkedList<T...
Iterating over every two elements in a list
... y in pairwise(l):
print "%d + %d = %d" % (x, y, x + y)
Or, more generally:
from itertools import izip
def grouped(iterable, n):
"s -> (s0,s1,s2,...sn-1), (sn,sn+1,sn+2,...s2n-1), (s2n,s2n+1,s2n+2,...s3n-1), ..."
return izip(*[iter(iterable)]*n)
for x, y in grouped(l, 2):
print...
Read .mat files in Python
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There is a nice package called mat4py which can easily be installed using
pip install mat4py
It is straightforward to use (from the website):
Load data from a MAT-file
The function loadmat loads all variables stored in the MAT-file into a simple...
What is object slicing?
...uestions/274626#274636 for an example of how slicing occurs during method calls (which underscores the danger a little better than the plain assignment example).
– Blair Conrad
Nov 8 '08 at 13:53
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