On 09/15/21 06:28, Marcos Pegoraro wrote: > Oracle and SQL Server have FOLLOWS and PRECEDES when defining trigger > execution order. Firebird has POSITION, which I like it more.
Between those two, I think my vote would come down the other way, assuming FOLLOWS and PRECEDES work the way I am guessing they do: you would be specifying the firing order between triggers whose relative order you care about, and leaving it unspecified between triggers whose relative order doesn't matter. I find that an appealing general solution that allows the machine to find a satisfactory order, and is less fussy than trying to manually create a total order for all of the triggers (even those whose relative order may not matter) by arbitrarily fussing with names or integers. It resembles similar constructs in lots of other things, like the way grammar precedences are specified [0] in SDF. It may be objected that this makes a trigger order that is less fully determined in advance, and can lead to issues that are harder to reason out if you forgot to specify a relative order that matters. But balancing that is that it may be easier in general to reason about just the relative orders that matter, undistracted by any that don't. In some settings, leaving unspecified the ones that don't may increase opportunities for optimization. (Not that I have any specific optimizations in mind for this setting.) One could even think about a test mode that would deliberately randomize the relative order between triggers where it hasn't been specified. Regards, -Chap [0] https://www.metaborg.org/en/latest/source/langdev/meta/lang/sdf3/reference.html#priorities