;>>> 20111219 03:42 PM -0800, Jim McNeely >>>>
Not if you are using innoDB tables. For these, you use INSERT and UPDATE triggers.
On Dec 19, 2011, at 11:58 AM, Hal
>>>>> 2011/12/19 11:30 -0800, Jim McNeely >>>>
> In the MySQL documentation, we find this tantalizing statement:
> "It is possible that in the case of a duplicate-key error, a storage engine may
> perform the REPLACE as an update rather than a delete plus insert, but the semantics are
> the same. There are no user-visible effects other than a possible difference in how the
> storage engine increments Handler_xxx status variables."
> Well, try it--but beware of these statements: "the semantics are the same. There are
> no user-visible effects other than a possible difference in how the storage engine
> increments Handler_xxx status variables."
> If accurate, the triggers are those of DELETE & INSERT, not UPDATE.
In my experimenting I find (version 5.5.8) that DELETE & INSERT are triggered, not
UPDATE. The statement "There are no user-visible effects..." is simply wrong. The
SQL-programmer has to be ready for either outcome.