Order of Select

Not what I'm asking really. A vendor has a query in which the column in the select statement does not pull from the first table(forget the where).  In looking at BOTH queries below. Which would perform better?

Select b.Name Id
  From appointments a
 join names b on a.SomeID=b.SomeID


Select b.Name Id
  From names b
 join appointments a on a.SomeID=b.SomeID

such "simple" query both shall run in the same explain plan, hence in the same performance

Are you sure? If we have 34,000,000 rows and multiple indexes both would perform the same?

yes, both would perform the same, normally. as the indexes are "static" (in terms of their existance), the sql engine will first see what indexes are there, which would be the most approriate for the query (checking what you give as input, what it will return as ouput, statistics by the table data and indexes etc, without going into details here), and find for both queries the same explain plan.

please just use the "estimate explain plan" for the 2 queries, it shall show you a graphical display, which should be the same for both. the number of "source records" does not matter.
however, based on server load, if the statistics based on input/ouput data might be very close to some "internal thresholds", your queries might indeed be run differently. but this is very unlikely.