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No Persistence provider for EntityManager named
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I am using Derby and it wasn't necessary to specify this (I did, but then removed it once I solved the problem, just to make sure). I was getting the error finally because persistence.xml was not in the src/META-INF folder, even though it had...
How to append a char to a std::string?
... It is more natural IMO for strings. push_back is container function, and a string is a specialized one in STL :)
– AraK
Sep 24 '09 at 14:38
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Python try…except comma vs 'as' in except
What is the difference between ',' and 'as' in except statements, eg:
5 Answers
5
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MySQL DISTINCT on a GROUP_CONCAT()
...n a string like:
test1 test2 test3 test1 test3 test4
(notice that test1 and test3 are duplicated) while the OP wants to return this string:
test1 test2 test3 test4
the problem here is that the string "test1 test3" is duplicated and is inserted only once, but all of the others are distinct to e...
Method to Add new or update existing item in Dictionary
... indexer setters of both classes call this.Insert(key, value, add: false); and the add parameter is responsible for throwing an exception, when inserting a duplicate key. So the behavior is the same for both classes.
share
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Linq to Entities join vs groupjoin
... [b1, b2]
C []
So Join produces a flat (tabular) result of parent and child values.
GroupJoin produces a list of entries in the first list, each with a group of joined entries in the second list.
That's why Join is the equivalent of INNER JOIN in SQL: there are no entries for C. While Group...
Storyboard doesn't contain a view controller with identifier
... edited Aug 9 '15 at 14:03
Andy Weinstein
2,38033 gold badges1515 silver badges2121 bronze badges
answered Jul 22 '12 at 23:29
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How can I get all the request headers in Django?
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According to the documentation request.META is a "standard Python dictionary containing all available HTTP headers". If you want to get all the headers you can simply iterate through the dictionary.
Which part of your code to do this depends on your exact requirement. Anypla...
Bash array with spaces in elements
...ferenced using ${name[subscript]}. ... If subscript is @ or *, the word expands to all members of name. These subscripts differ only when the word appears within double quotes. If the word is double-quoted, ${name[*]} expands to a single word with the value of each array member separated by the firs...
Why can't my program compile under Windows 7 in French? [closed]
I'm running Windows 7 French and I'm trying to compile this really basic program, but Visual Studio is being stubborn and refuses to comply. I also tried compiling it with both GCC 4.7 and Clang trunk on Coliru and I get more or less the same errors (output is below the code), though I think Colir...