Re: BUG #12789: Views defined with VALUES lose their column names when dumped

Andrew Gierth <andrew(at)tao11(dot)riddles(dot)org(dot)uk> writes:
> For future reference and as a simpler testcase than the one in the
> script:

> # create view v1(a) as values (1);
> CREATE VIEW

> # select pg_get_viewdef('v1'::regclass);
> pg_get_viewdef
> ----------------
> VALUES (1);

> Notice that the column name "a" is lost. Since pg_dump and so on rely on
> pg_get_viewdef, dump and restore changes the column name back to
> "column1".

> The culprit is obviously in ruleutils.c:
> get_simple_values_rte/get_values_def, which mistakenly thinks it only
> has to deal with the result of transformValuesClause(), not considering
> that the result of transformValuesClause might have been further
> mogrified by DefineView. Treating this case as not being "simple" might
> be one approach... not sure of the best way to detect that.

Yeah --- we can check to see if the tlist resnames match what's in the
RTE. It turns out that get_from_clause_item() is also buggy: apparently
the RTE_VALUES path through that has never been exercised, or at least
nobody has pointed out to us that it prints bad syntax. I'm guessing
that up to now, get_simple_values_rte *always* succeeds for situations
involving a VALUES RTE and so we never got there. The attached seems
to fix it though.

regards, tom lane