Re: pg_dumpall --exclude-database option

The comment in expand_dbname_patterns is ungrammatical and mentions
"OID" rather than "name", so I suggest

/*
* The loop below might sometimes result in duplicate entries in the
* output name list, but we don't care.
*/

I'm not sure this is grammatical either:
exclude databases whose name matches PATTERN
I would have written it like this:
exclude databases whose names match PATTERN
but I'm not sure (each database has only one name, of course, but aren't
you talking about multiple databases there?)

Other than that, the patch seems fine to me -- I tested and it works as
intended.

Personally I would say "See also expand_table_name_patterns" instead of
"This is similar to code in pg_dump.c for handling matching table names.",
as well as mention this function in expand_table_name_patterns' comment.
(No need to mention expand_schema_name_patterns, since these are
adjacent.) But this is mostly stylistic and left to your own judgement.

In the long run, I think we should add an option to processSQLNamePattern
to use OR instead of AND, which would fix both this problem as well as
pg_dump's. I don't think that's important enough to stall this patch.

--
Álvaro Herrera https://www.2ndQuadrant.com/
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