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From Rainer Döbele <doeb...@esteam.de>
Subject re: How to tell that a rows is UNIQUE ?
Date Wed, 18 May 2011 19:26:16 GMT
Hi exxos,

I don't quite understand your question.
What do you consider a unique column?

Some databases allow integer columns that are automatically populated from a sequence (e.g.
identity columns in Microsoft SQL).

Another feature in Microsoft sql is the data type "uniqueidentifier" which is a guid that
will be automatically generated for each row.

For those two cases Empire-db offers the data types DataType.AUTOINC and DataType.UNIQUEID.

The exact implementation however is database specific. The Oracle driver e.g. will create
a number column and automatically create a sequence for AutoInc columns (on DDL generation).

Does this answer help you?

Regards
Rainer

 
Exxos wrote:
> from: exxos [mailto:hatufr@gmail.com] 
> to: empire-db-user@incubator.apache.org
> re: How to tell that a rows is UNIQUE ?
>
> Hello,
>
> At the colomn declartion in DBTable, how to tell that a colomn is unique ?
> (I'm not talking about primaries keys)
>
> Regards,
> exxos.

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