Any way to index multiple columns?

[Jonathan Feinberg <jd...@us.ibm.com>]

Is there any way to cause the OpenJPA schema builder to emit an index across multiple columns? My attempt,
 @Column(columnDefinition = "bytea")
 @Index(name = "i_owner_md5", columnNames = { "owner_id, md5" })
 public byte[] getMd5()
 {
  return md5;
 }
is silently misinterpreted, in that only the annotated field (md5) gets indexed.

Thanks,
-- 

Re: Any way to index multiple columns?

[Marc Prud'hommeaux <mp...@apache.org>]

Jonathan-

It looks like we indeed do ignore the columnNames field of the index.  
This is a bug, and I've entered it at:

   https://issues.apache.org/jira/browse/OPENJPA-223

I don't think there is a workaround, unless the index is unique, in  
which case you can use the JPA standard  
javax.persistence.UniqueConstraint annotation on the @Table  
annotation (which allows you to specify multiple columns, and which  
we appear to respect).



On Apr 18, 2007, at 11:56 AM, Jonathan Feinberg wrote:

> Is there any way to cause the OpenJPA schema builder to emit an  
> index across multiple columns? My attempt,
>  @Column(columnDefinition = "bytea")
>  @Index(name = "i_owner_md5", columnNames = { "owner_id, md5" })
>  public byte[] getMd5()
>  {
>   return md5;
>  }
> is silently misinterpreted, in that only the annotated field (md5)  
> gets indexed.
>
> Thanks,
> --