On Mon, Nov 24, 2014 at 3:26 PM, Thom Brown <t...@linux.com> wrote: > I haven't seen this mentioned anywhere (although it may have as I haven't > read through the entire history of it), but would others find it useful to > have ALTER SYSTEM support comments?
Oh, please no. The main thing that caused us to have no way of modifying postgresql.conf via SQL for so many years is that it's not clear how you can sensibly rewrite a file with comments in it. For example, the default postgresql.conf file has stuff like this in it: #variable = someval If variable gets set to a non-default value, you might want to uncomment that line, but now you have to parse the comments, which will be tedious and error-prone and sometimes make stupid decisions: #Back in days of yore when dinosaurs ruled the earth, we had #autovacuum_naptime=1h, but that turned out to be a bad idea. # #autovacuum_naptime=1min It's hard for a non-human to know that the second one is the one that you should uncomment. There are lots of other problems that arise, too; this is just an example. It would perhaps be OK to have comments in postgresql.conf.auto if they were designated in some way that told us which specific comment was associated with which specific setting. But we need to be very careful not to design something that requires us to write a parser that can ferret out human intent from context clues. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
