[postgis-users] sync geometry with attributes

[Markus Schaber]

Hi, Bruce,

Bruce Rindahl <rindahl at lrcwe.com> wrote:

> I think triggers may not be the answer here.  If you define the trigger 
> as updating the geometry whenever the attributes change  then if you 
> change the geometry the trigger will always reset the geometry to the 
> old value.  The same thing happens if the trigger goes the other way.  I 
> think what ever you use to update the geometry needs to also update the 
> attributes.

A trigger has both the old and the new row, so it can decide whether
the geometry or the attributes have changed, and update the other one.
It can even just pass the data along when both are changed, assuming
that the application will do the correct thing in this case.


Regards,
Markus

-- 
Markus Schaber | Logical Tracking&Tracing International AG
Dipl. Inf.     | Software Development GIS

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