"Kevin Grittner" <kevin.gritt...@wicourts.gov> writes: > Tom Lane <t...@sss.pgh.pa.us> wrote: >> 3. Or, perhaps we could change recordDependencyOnSingleRelExpr so >> that it generates a whole-table dependency on the target relation >> even if there are no Vars in the expression. This would make it >> act much more like the regular-query context that >> find_expr_references_walker is expecting --- in essence, since >> we're fabricating a single-element rtable for >> find_expr_references_walker to work with, we should fabricate the >> implied whole-table dependency entry too. But that seems a bit >> weird too, and in particular it's not obvious whether to do that >> if in fact the expression is empty, or doesn't contain any Var at >> all. > This one seems sensible *if* you assume that by the time it is > called there is a known dependency on the particular relation -- for > example, you are dealing with an index on that relation. Is that a > reasonable restriction on the use of the > recordDependencyOnSingleRelExpr function? If this was done, would > it allow simplification of the index_create code you showed in #1?
Well, it doesn't really improve matters for the index_create code. What it basically accomplishes so far as that's concerned is to guarantee that there will be a (likely redundant) whole-table dependency; which we could equally well guarantee from the other end, a la my fix #1. After sleeping on it I'm pretty well convinced that fix #1 is the way to go; it's simple and gets rid of some code that was just trying to be too cute. If we had a clear example of some future use of recordDependencyOnSingleRelExpr that would require a different behavior for the expression-dependency-extraction code, I might want to change that code instead; but we don't. (Obviously some more comments around the dependency-extraction code will be a good idea in any case.) regards, tom lane -- Sent via pgsql-bugs mailing list (pgsql-bugs@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-bugs