Emmanuel Cecchet wrote:
Greg Smith wrote:
On Fri, 11 Sep 2009, Emmanuel Cecchet wrote:
I guess the problem with extra or missing columns is to make sure
that you know exactly which data belongs to which column so that you
don't put data in the wrong columns which is likely to happen if
this is fully automated.
Allowing the extra column case is easy: everwhere in copy.c you find
the error message "extra data after last expected column", just
ignore the overflow fields rather than rejecting the line just based
on that. And the default information I mentioned you might want to
substitute for missing columns is already being collected by the code
block with the comment "Get default info if needed".
If I understand it well, you expect the garbage to be after the last
column. But what if the extra or missing column is somewhere upfront
or in the middle? Sometimes you might have a type conflict problem
that will help you detect the problem, sometimes you will just insert
garbage. This might call for another mechanism that would log the
lines that are automatically 'adjusted' to be able to rollback any
mistake that might happen during this automated process.
Garbage off to the right is exactly the case that we have. Judging from
what I'm hearing a number of other people are too.
Nobody suggests that a facility to ignore extra columns will handle
every case. It will handle what increasingly appears to be a common case.
cheers
andrew
--
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers
