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id of a record

 
Daniel Vogt
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in my database interface i have the following method-declaration:

//Creates a new record in the database (possibly reusing a deleted
//entry). Inserts the given data, and returns the record number of the
//new record.
public int create(String[] data) throws DuplicateKeyException;

and my databasedefinition has no "primary key". the only thing what i have is a unique name. and which one should be the record number? should i generate a map with the id's and the unique name? or maybe a map with the id of the record and with the start-position in the db-file?

regards,
[ April 09, 2007: Message edited by: Daniel Vogt ]
 
Lucy Hummel
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Hi,

May I ask you to read the



naming guideline again and update you display name accordingly?

Furthermore, if you have a kind of primary key, that is great. I do not have it. So mapping that key to the file position sounds a pretty good idea/solution.

Why do I not have a primary key?!
 
Mihai Radulescu
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IntelliJ IDE Java Linux
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Daniel,

The DuplicateKeyException can be throw if you can define a unicity criteria, and this depend on your database structure. Even if this sound strange there are some situation where you can not define a reliable unicity criteria and in this case you can not throw the DuplicateKeyException, but you need to document your decision.


regards M.
 
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