Hi, Mark.

Apologies for the delay, but I got trapped by RL.

I think you are right that the trigger is the issue because it tests two TIMESTAMP fields to see which is greater.

BEGIN
UPDATE new_data set A1=NEW.A1, A2=NEW.A2, DateTime_Stamp=NEW.DateTime_Stamp
WHERE MAC=NEW.MAC AND DateTime_Stamp<=NEW.DateTime_Stamp;
end

Since NULL is a lack of data, I assume that would fail. I haven't put in a test for NULL yet. Would a simple OR suffice?? For ExampleFrom sd@... Wed Aug 12 01:05:36 2009
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