On Thu, Oct 8, 2009 at 3:30 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: > Alvaro Herrera <alvhe...@commandprompt.com> writes: >> Tom Lane escribió: >> Does it affect how is it going to look in EXPLAIN output? > > Hmm, I suppose there's not any law that says EXPLAIN has to print the > same name we use internally. The explain output could say "Insert", > "Update", or "Delete" independently of what we call the node type.
It already does, in text mode. > That would take away about 50% of my objection to the node name, > though on balance I still think "Dml" is a poor choice since plan > node names are typically verbs. Agreed. > One issue is whether it would be confusing for implementors if the > explain output is completely unrelated to the internal name. We could > do something like "InsertTable" or "ModifyTable Insert", but both of > these look a bit ugly from a user's standpoint I think. > > I notice also that the patch has chosen to represent Dml in XML/JSON > explain output as Node Type = Dml with an entirely new attribute > Operation to indicate Insert/Update/Delete. Do we really want to > go there? Adding single-purpose attributes doesn't seem like a great > idea. Well, I was the one who suggested doing it that way, so you can blame me for that, but it is consistent with how we've handled other things, like setops and jointypes: the details get moved to another tag so as to avoid an explosive growth in the number of node types that clients must be prepared for. > While we're discussing explain output ... what about triggers? > An important aspect of this change is that at least the row-level > triggers are now going to be charged as runtime of the > Dml-or-whatever-we-call-it node. Should we rearrange the explain > output so that the printout for trigger runtimes is associated > with those nodes too? If so, what about statement-level triggers? That's not a bad idea, though it wouldn't bother me much if we left it for a follow-on patch. ...Robert -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
