Re: explain refactoring v4

Robert Haas <robertmhaas@gmail.com> writes:
> OK, here it is again.  Changes are the same as the previous version,
> but this one should apply cleanly after today's pgindent run.

As I was poking through this I noticed that it makes at least one small
change in the output format: what had been "Subquery Scan ss" will now
be "Subquery Scan on ss", because of the unification of code that wasn't
really entirely consistent into one subroutine ExplainScanTarget.

This is not likely to matter to human readers but it might to programs.
OTOH we presumably expect programs to migrate to using a more
program-friendly EXPLAIN output format with 8.5.

Does anyone have strong feelings about whether we need to be
bug-compatible with the old formatting?
        regards, tom lane