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Good tool to visualise database schema? [closed]
Are there any good tools for visualising a pre-existing database schema? I'm using MySQL if it matters.
20 Answers
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Is there an opposite of include? for Ruby Arrays?
...
if @players.exclude?(p.name)
...
end
ActiveSupport adds the exclude? method to Array, Hash, and String. This is not pure Ruby, but is used by a LOT of rubyists.
Source: Active Support Core Extensions (Rails Guides)
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Purpose of Unions in C and C++
... relatively large number of people, which is what hotels are for.
That's exactly what union does. If you know that several objects in your program hold values with non-overlapping value-lifetimes, then you can "merge" these objects into a union and thus save memory. Just like a hotel room has at mo...
OOP vs Functional Programming vs Procedural [closed]
...e in common with each other (as in Lisp and Scheme) while offering more flexibility in terms of how functions are actually used. Algorithms tend also to be defined in terms of recursion and composition rather than loops and iteration.
Of course, the language itself only influences which style is pr...
How to enumerate an enum with String type?
For example, how can I do something like:
42 Answers
42
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Split list into multiple lists with fixed number of elements
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Or if you want to make your own:
def split[A](xs: List[A], n: Int): List[List[A]] = {
if (xs.size <= n) xs :: Nil
else (xs take n) :: split(xs drop n, n)
}
Use:
scala> split(List(1,2,3,4,5,6,"seven"), 4)
res15: List[List[Any]] = List(List(1, 2, 3, 4), List(5...
Where to learn about VS debugger 'magic names'
...removes, we emit debug info for it anyway into the PDB. We stuck the suffix __Deleted$ onto such variables so that the debugger knows that they were in source code but not represented in the binary.
Temporary variable slots allocated by the compiler are given names with the pattern CS$X$Y, where X...
Why does Math.round(0.49999999999999994) return 1?
...gram you can see that each value slightly less than .5 is rounded down, except for 0.5 .
5 Answers
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What issues should be considered when overriding equals and hashCode in Java?
...:
equals() (javadoc) must define an equivalence relation (it must be reflexive, symmetric, and transitive). In addition, it must be consistent (if the objects are not modified, then it must keep returning the same value). Furthermore, o.equals(null) must always return false.
hashCode() (javadoc) m...
Delete all documents from index/type without deleting type
...ll it should do what you are looking for, something like this (using your example):
curl -XDELETE 'http://localhost:9200/twitter/tweet/_query' -d '{
"query" : {
"match_all" : {}
}
}'
Or you could just delete the type:
curl -XDELETE http://localhost:9200/twitter/tweet
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