Re: FOR EACH ROW triggers on partitioned tables

On 2/15/18 16:55, Alvaro Herrera wrote:
> Amit Langote wrote:
>> Do you mean to fire these triggers only if the parent table (not a child
>> table/partition) is addressed in the DML, right? If the table directly
>> addressed in the DML is a partition whose parent has a row-level trigger,
>> then that trigger should not get fired I suppose.
>
> No, I think that would be strange and cause data inconsistencies.
> Inserting directly into the partition is seen as a performance
> optimization (compared to inserted into the partitioned table), so we
> don't get to skip firing the triggers defined on the parent because the
> behavior would become different. In other words, the performance
> optimization breaks the database.
>
> Example: suppose the trigger is used to maintain an audit record trail.

Although this situation could probably be addressed by not giving
permission to write directly into the partitions, I can't think of an
example where one would want a trigger that is only fired when writing
into the partition root rather than into the partition directly.

--
Peter Eisentraut http://www.2ndQuadrant.com/
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