On Wed, 01 Feb 2023 11:47:23 -0500 Tom Lane <t...@sss.pgh.pa.us> wrote:
> Yugo NAGATA <nag...@sraoss.co.jp> writes: > > Antonin Houska <a...@cybertec.at> wrote: > >> While working on [1] I noticed that if RLS gets enabled, the COPY TO > >> command > >> includes the contents of child table into the result, although the > >> documentation says it should not: > > > I think this is a bug because the current behaviour is different from > > the documentation. > > I agree, it shouldn't do that. > > > When RLS is enabled on a table in `COPY ... TO ...`, the query is converted > > to `COPY (SELECT * FROM ...) TO ...` to allow the rewriter to add in RLS > > clauses. This causes to dump the rows of child tables. > > Do we actually say that in so many words, either in the code or docs? > If so, it ought to read `COPY (SELECT * FROM ONLY ...) TO ...` > instead. (If we say that in the docs, then arguably the code *does* > conform to the docs. But I don't see it in the COPY ref page at least.) The documentation do not say that, but the current code actually do that. Also, there is the following comment in BeginCopyTo(). * With row-level security and a user using "COPY relation TO", we * have to convert the "COPY relation TO" to a query-based COPY (eg: * "COPY (SELECT * FROM relation) TO"), to allow the rewriter to add * in any RLS clauses. Maybe, it is be better to change the description in the comment to "COPY (SELECT * FROM ONLY relation) TO" when fixing the bug. Regards, Yugo Nagata -- Yugo NAGATA <nag...@sraoss.co.jp>