Subject | old and new variables in sequential triggers |
---|---|
Author | Gerhardus Geldenhuis |
Post date | 2002-10-16T11:32:51Z |
Hi
I did an experiment on old and new values in triggers and I just want to
know if my "findings" is correct.
I have written two before update triggers one with position 1 and the
other with position 2.
My start field value is 1.
the trigger code is
The value I typed was 30.
if (new.k3=10) then
new.k3=20
I write the old and new variable values in the second trigger to a table.
The second triggers old value was 1 and the new value was 20.
My deduction is that the old value for triggers following each other
will always be the value it was before the first trigger fired and
the new value will be whatever it is changed to in the previous trigger.
Also the old value for after update will be the value before any trigger
was fired and the new value for after update will whatever it was
changed to in the last after update trigger that edited the new
variable, with the difference that this value will not write back to the
table.
Groete
Gerhardus
I did an experiment on old and new values in triggers and I just want to
know if my "findings" is correct.
I have written two before update triggers one with position 1 and the
other with position 2.
My start field value is 1.
the trigger code is
The value I typed was 30.
if (new.k3=10) then
new.k3=20
I write the old and new variable values in the second trigger to a table.
The second triggers old value was 1 and the new value was 20.
My deduction is that the old value for triggers following each other
will always be the value it was before the first trigger fired and
the new value will be whatever it is changed to in the previous trigger.
Also the old value for after update will be the value before any trigger
was fired and the new value for after update will whatever it was
changed to in the last after update trigger that edited the new
variable, with the difference that this value will not write back to the
table.
Groete
Gerhardus