Robert Haas <robertmh...@gmail.com> writes: > Just out of curiosity, does this change create a dump-and-reload > hazard? Like if I pg_upgrade my cluster, will the output of pg_dump > potentially be sufficiently under-parenthesized that reload will > create a non-equivalent database?
No. Had there been any such hazard, I would not have been nearly as enthused about this project. In the first place, pg_dump disables ruleutils' pretty-printing heuristics, so that you always get fully parenthesized expressions no matter what. I insisted on that years ago, in the expectation that we might someday need to do things like this patch; it's always acted that way, in every release that had any pretty-printing ability at all. For example, regression=# create view vv as select unique1 + unique2*four as x from tenk1; CREATE VIEW regression=# \d+ vv View "public.vv" Column | Type | Modifiers | Storage | Description --------+---------+-----------+---------+------------- x | integer | | plain | View definition: SELECT tenk1.unique1 + tenk1.unique2 * tenk1.four AS x FROM tenk1; regression=# \q $ pg_dump -t vv regression ... CREATE VIEW vv AS SELECT (tenk1.unique1 + (tenk1.unique2 * tenk1.four)) AS x FROM tenk1; In the second place, AFAICS ruleutils' heuristics do not know anything about any of the constructs affected by this patch, and so they'll be fully parenthesized anyway, even in pretty-printed output. For example: regression=# create view vvv as select 1+2 is distinct from 42 as q; CREATE VIEW regression=# \d+ vvv View "public.vvv" Column | Type | Modifiers | Storage | Description --------+---------+-----------+---------+------------- q | boolean | | plain | View definition: SELECT (1 + 2) IS DISTINCT FROM 42 AS q; The parens are unnecessary, but ruleutils doesn't know that, so it puts them in. regards, tom lane -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers