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Difference Between One-to-Many, Many-to-One and Many-to-Many?
Ok so this is probably a trivial question but I'm having trouble visualizing and understanding the differences and when to use each. I'm also a little unclear as to how concepts like uni-directional and bi-directional mappings affect the one-to-many/many-to-many relationships. I'm using Hibernate ri...
Get generated id after insert
I'm using the SQLite with Android, and I want to know the best way to get the generated id of the row I inserted.
5 Answers...
MySQL Insert into multiple tables? (Database normalization?)
I tried searching a way to insert information in multiple tables in the same query, but found out it's impossible?
So I want to insert it by simply using multiple queries i.e;
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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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Distributed sequence number generation?
I've generally implemented sequence number generation using database sequences in the past.
13 Answers
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How do you list the primary key of a SQL Server table?
..., how do you list the primary key of a table with T-SQL? I know how to get indexes on a table, but can't remember how to get the PK.
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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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Cast Int to enum in Java
What is the correct way to cast an Int to an enum in Java given the following enum?
17 Answers
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How to COUNT rows within EntityFramework without loading contents?
I'm trying to determine how to count the matching rows on a table using the EntityFramework.
7 Answers
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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....