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From Rick Hillegas <rick.hille...@oracle.com>
Subject Re: Accessing SYSXPLAIN tables via java methods?
Date Thu, 27 May 2010 18:31:06 GMT
Hi Nirmal,

I'm not sure that I understand your question. Bear in mind that you will 
want the tool to be able to operate across the network (as ij does). 
When operating across the network, you can't directly call engine entry 
points because the engine isn't running in the same VM as the client. 
You may find it helpful to think about the tool as a piece of remote, 
client code which runs in New York and scrapes query plans out of an 
engine which runs in London.

Hope this is useful,
-Rick

Nirmal Fernando wrote:
> Hi All,
>
> In the ij tool, if we need to query SYSXPLAIN tables, we should call
> some methods before and after.
>
> eg: [0]
>
> To cause Derby to record statistics about statement execution in the
> SYSXPLAIN_* database tables in the schema named 'MY_STATS':
>
>         call syscs_util.syscs_set_runtimestatistics(1);
>         call syscs_util.syscs_set_xplain_schema('MY_STATS');
>
>         select country from countries;
>
>         call syscs_util.syscs_set_runtimestatistics(0);
>         call syscs_util.syscs_set_xplain_schema('');
>
>
> My question is can we call these methods in the code of a new tool
> (like ij) as java methods?
>
>
> References:
>
> [0] http://db.apache.org/derby/docs/dev/ref/rref_syscs_set_xplain_schema.html#rref_syscs_set_xplain_schema
>
>
> Thanks.
>
>   


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