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How to count the number of occurrences of an element in a List
...<String, Long> counts =
list.stream().collect(Collectors.groupingBy(e -> e, Collectors.counting()));
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Entity Framework and Connection Pooling
... about NHibernate Session but the idea is same.
Edit:
When you use EF it by default loads each entity only once per context. The first query creates entity instace and stores it internally. Any subsequent query which requires entity with the same key returns this stored instance. If values in the ...
When is JavaScript's eval() not evil?
...premise of your question - that eval() is "evil". The word "evil", as used by programming language people, usually means "dangerous", or more precisely "able to cause lots of harm with a simple-looking command". So, when is it OK to use something dangerous? When you know what the danger is, and when...
Multiple columns index when using the declarative ORM extension of sqlalchemy
...ns/declarative/… "Keyword arguments can be specified with the above form by specifying the last argument as a dictionary"
– zzzeek
Oct 23 '17 at 16:18
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Ruby on Rails production log rotation
What is the best way to enable log rotation on a Ruby on Rails production app?
6 Answers
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Does C++ support 'finally' blocks? (And what's this 'RAII' I keep hearing about?)
... other classes. When the owning class' is destructed, the resource managed by the RAII class gets released because the destructor for the RAII-managed class gets called as a result. This means that when you use RAII for all members in a class that manage resources, you can get away with using a ver...
Difference between Select and ConvertAll in C#
...on all IEnumerable<T> objects whereas ConvertAll is implemented only by List<T>. The ConvertAll method exists since .NET 2.0 whereas LINQ was introduced with 3.5.
You should favor Select over ConvertAll as it works for any kind of list, but they do the same basically.
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How to convert an int array to String with toString method in Java [duplicate]
...ments, enclosed in square brackets ("[]"). Adjacent elements are separated by the characters ", " (a comma followed by a space). Elements are converted to strings as by String.valueOf(int). Returns "null" if a is null.
shar...
What's the difference between ConcurrentHashMap and Collections.synchronizedMap(Map)?
I have a Map which is to be modified by several threads concurrently.
19 Answers
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MongoDB: Is it possible to make a case-insensitive query?
...earching with regex's case insensitive /i means that mongodb cannot search by index, so queries against large datasets can take a long time.
Even with small datasets, it's not very efficient. You take a far bigger cpu hit than your query warrants, which could become an issue if you are trying to...