Re: Release changes - Mailing list pgsql-hackers

How are statement level triggers supposed to work?  Are they just
triggers deferred until the end of the statement?  You mentioned access
to the affected rows, but I don't understand how that is supposed to
happen.


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Andreas Pflug wrote:
> Thinking hard about wording...
> 
> Add partially implemented FOR EACH STATEMENT statement-level triggers (Neil Conway)
> 
> 
> which doesn't look nice but expresses what's implemented. Taken from the 
> CREATE TRIGGER FOR EACH STATEMENT documentation, a user would think he 
> could do the same stuff as on lets say MSSQL, in a way known from 
> row-level triggers. The example trigger-example.html seems to be 
> non-statement-level trigger aware. Chapter 37 is quite misleading, for 
> example recursive triggers are mentioned "programmer's responsibility to 
> avoid infinite recursion"suggesting there would be a way to know about 
> the affected rows...
> 
> Actually, I'd consider not to mention statement triggers at all. In the 
> current state, they will provoke some annoyance if people try to use 
> them. We will see them on the mailing lists, seeking for what's 
> currently not available...
> 
> Regards,
> Andreas
> 
> Bruce Momjian wrote:
> 
> >Do you have suggested wording?
> >
> >---------------------------------------------------------------------------
> >
> >Andreas Pflug wrote:
> >  
> >
> >>Bruce Momjian wrote:
> >>
> >>    
> >>
> >>>Here are the changes for 7.4.  I am looking for any improvements.  This
> >>>will be adjusted as we move through beta.
> >>>
> >>>---------------------------------------------------------------------------
> >>>Add FOR EACH STATEMENT statement-level triggers (Neil Conway)
> >>>
> >>>      
> >>>
> >>AFAICS the current implementation still doesn't have a way to access the 
> >>affected rowset, so it'a pretty much like a SELECT without a WHERE. This 
> >>restricts the usability of statement-level triggers to very limited 
> >>cases. IMHO it's not a good idea to announce an incompletely implemented 
> >>feature.
> >>
> 
> 
> 
> 

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