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Re: Help for a create un trigger
Posted by: Phillip Ward
Date: February 06, 2023 08:36AM


I need to fill in a data_diff field to warn how many days I do not receive communication from the device

No, you don't.
This time-based value will change all the time (pun intended).

This is data that can be derived from other data that you already have, i.e. the date on which you last received data from each device:

, now() - data_ultimo intervallo 
from autotest_ping a 
inner join 
  select id_Autotest 
  , max( data_arrivo ) data_ultimo 
  from autotest_ping
  group by id_Autotest
) b 
on a.id_Autotest = b.id_Autotest
order by 2 desc, 1 ;

Of coourse, an index on id_Autotest and data_arrivo would help this query a lot.

Regards, Phill W.

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Written By
February 05, 2023 08:59AM
Re: Help for a create un trigger
February 06, 2023 08:36AM

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