I am trying to create a composite key that mimicks the set of PrimaryKeys in the built in MySQL.DB table.
I am writing a new app with Rails so I have an id column on every table. What is the best practice for enforcing domain constraints using foreign keys? I\'ll outline my thoughts and frustration.
I\'m not sure how to use composite key. My Categories table has CategoryId (PK,FK), Langua开发者_C百科geId (PK,FK), CategoryName
Is it possible to break the composite key 开发者_JAVA百科of a table and use one of them as a primary key for other table? If yes, then please tell me how can I do it?Generally you use a composite key
I\'ve followed the instructions here, installing the composite_primary_keys gem via sudo gem install composite_primary_keys
I have the following schema (* means primary key): languages id* english_name native_name native_to_target_languag开发者_如何学编程e
This question already has an answer here: nHibernate Composite Key Class Type Mismatch (1 answer) Closed 2 years ago.
OK, so here is the problem. Its not even as crazy as the guy who wants to map m:n with different column counts in his PKs.
So I have this table with a composite key, basically \'userID\'-\'data\' must be unique (see my other question SQL table - semi-unique row?)
Hey, i\'m trying to delete an entity of the following structure from an Oracle 10g tables: class Record
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