On Fri, Mar 13, 2015 at 11:26 AM, Pavel Stehule <pavel.stehule@gmail.com> wrote: > we found possible bug in pg_dump. It raise a error only when all specified > tables doesn't exists. When it find any table, then ignore missing other. > > /usr/local/pgsql/bin/pg_dump -t Foo -t omega -s postgres > /dev/null; echo > $? > > foo doesn't exists - it creates broken backup due missing "Foo" table > > [pavel@localhost include]$ /usr/local/pgsql/bin/pg_dump -t Foo -t omegaa -s > postgres > /dev/null; echo $? > pg_dump: No matching tables were found > 1 > > Is it ok? I am thinking, so it is potentially dangerous. Any explicitly > specified table should to exists.
Keep in mind that the argument to -t is a pattern, not just a table name. I'm not sure how much that affects the calculus here, but it's something to think about.
yes, it has a sense, although now, I am don't think so it was a good idea. There should be some difference between table name and table pattern.
There is...a single table name is simply expressed as a pattern without any wildcards. The issue here is that pg_dump doesn't require that every instance of -t find one (or more, if a wildcard is present) entries only that at least one entry is found among all of the patterns specified by -t.
I'll voice my agreement that each of the -t specifications should find at least one table in order for the dump as a whole to succeed; though depending on presented use cases for the current behavior I could see allowing the command writer to specify a more lenient interpretation by specifying something like --allow-missing-tables.
Command line switch formats don't really allow you to write "-t?" to mean "I want these table(s) if present", do they? I guess the input itself could be interpreted that way though; a leading "?" is not a valid wildcard and double-quotes would be required for it to be a valid table name.