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How to convert a List into a comma separated string without iterating List explicitly [dupli
Now i want an output from this list as 1,2,3,4 without explicitly iterating over it.
13 Answers
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Postgres: How to do Composite keys?
I cannot understand the syntax error in creating a composite key. It may be a logic error, because I have tested many varieties.
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In CMake, how can I test if the compiler is Clang?
We have a set of cross-platform CMake build scripts , and we support building with Visual C++ and GCC .
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ViewParam vs @ManagedProperty(value = “#{param.id}”)
What is the difference between defining View Params like this:
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SQL RANK() versus ROW_NUMBER()
I'm confused about the differences between these. Running the following SQL gets me two idential result sets. Can someone please explain the differences?
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Foreign keys in mongo?
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You may be interested in using a ORM like Mongoid or MongoMapper.
http://mongoid.org/docs/relations/referenced/1-n.html
In a NoSQL database like MongoDB there are not 'tables' but collections. Documents are grouped inside Collections....
Build vs new in Rails 3
In the Rails 3 docs , the build method for associations is described as being the same as the new method, but with the automatic assignment of the foreign key. Straight from the docs:
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How to change the foreign key referential action? (behavior)
I have set up a table that contains a column with a foreign key, set to ON DELETE CASCADE (delete child when parent is deleted)
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How to implement has_many :through relationships with Mongoid and mongodb?
Using this modified example from the Rails guides , how does one model a relational "has_many :through" association using mongoid?
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How to combine class and ID in CSS selector?
If I have the following div:
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