Re: identity column behavior in WHEN condition for BEFORE EACH ROWtrigger

On 2019-10-03 16:08, Suraj Kharage wrote:
> It is been observed that when we define the generated columns in WHEN
> condition for BEFORE EACH ROW trigger then server throw an error from
> CreateTrigger().

> whereas, for identity columns, server allows us to create trigger for
> same and trigger gets invoked as defined. Is this behavior expected? or
> we need to restrict the identity columns in such scenario because anyone
> one override the identity column value in trigger.

This is per SQL standard: Identity columns are assigned before triggers,
generated columns are computed after BEFORE triggers.

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