Bruce Momjian wrote: > 1. What percentage speedup is the _average_ user going to get? You > have to consider people who will use indirect indexes who get no benefit > or a net slowdown, and users who will get a benefit. > > 2. What percentage of users are going to use indirect indexes? > > So, for #1 you might have users who are getting +1%, +50%, and -20%, so > maybe +10% average, and for #2 you might have 0.1%. When you multiply > them out, you get 0.01% average improvement per installation, which is > very small. Obviously, these are just wild guesses, but this is just to > make a point.
Perhaps not many users will require indirect indexes; but for those that do, the feature might be invaluable. We don't do only things that benefit everybody -- some features are there to satisfy small populations ("snapshot too old" is a recent example). We should of course do, and perhaps even favor doing things that benefit everybody, but should also do the other things. -- Álvaro Herrera https://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers