db-derby-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Andreas Korneliussen <Andreas.Kornelius...@Sun.COM>
Subject Re: [jira] Updated: (DERBY-231) "FOR UPDATE" required for updatable result set to work
Date Wed, 09 Nov 2005 11:42:57 GMT
Daniel John Debrunner wrote:
> Andreas Korneliussen wrote:
> 
> 
>>I am a bit curious about the statement about improving the JDBC
>>updatable result set implementation to not use positioned updates.
>>
>>Did you mean that an improvement could be to not base JDBC updatable
>>resultsets on positioned updates at all, and instead invent another
>>mechanism. If so, do you have any specific ideas on this ?
> 
> 
> It was just a vague idea. It seems somewhat inefficient for an updatable
> ResultSet to create a SQL statement, have that parsed & compiled in
> order to perfom an update or delete etc. However,  the use of SQL is a
> great example of re-use, especially as the problem looks simple 'update
> the current row', but in fact is complicated. The update must determine
> which triggers are to be invoked, which constraints to be checked etc.
> etc. This of course is handled automatically through the use of SQL.
> Maybe, just maybe, the code could be re-factored to allow updateable
> ResultSets to avoid the SQL parsing step but that's the limit of what
> I've thought about.
> 
> 
>>We are thinking of coninuing using positioned updates when doing
>>scrollable updatable resultsets - that is why I am asking.
> 
> 
> You should continue on your current path. I'm not working on this at all.
> 
> The general point I was trying to make it that testing user visible
> functionality implictly due to implementation knowledge is not a good
> practice. Test as we intend the users to use it, not indirectly through
> a different mechanism that might effect things somehow.
> 
I agree with this point -  thanks for the clarifications.

-- Andreas

Mime
View raw message