On Mon, Feb 14, 2011 at 11:51, Stephen Frost <sfr...@snowman.net> wrote: >> It would be awfully nice if we could inject something into the csvlog >> output format that would let client programs know which fields are >> present. This would be especially useful for people writing tools >> that are intended to work on ANY PG installation, rather than just, >> say, their own. I'm not sure if there's a clean way to do that, >> though. > > Added csvlog_header GUC to allow the user to ask for the header to be > printed at the top of each log file. If and when an option is added to > PG's COPY to respect the header, this should resolve that issue.
We need to design csvlog_header more carefully. csvlog_header won't work if log_filename is low-resolution, ex. log-per-day. It's still useful when a DBA reads the file manually, but documentation would better. Or, should we skip writing headers when the open log file is not empty? It works unless when csvlog_fields is modified before restart, and also on logger's crash and restart, though it's a rare case. A few comments and trivial issues: * It might be my misunderstanding, but there was a short description for %U for in log_line_prefix in postgresql.conf, right? Did you remove it in the latest version? * The long csvlog_fields default is a problem also in postgresql.conf, but we have no solution for the issue... The current code is the best for now. * In assign_csvlog_fields(), we need to cleanup memory and memory context before return on error. + /* check if no option matched, and if so, return error */ + if (curr_option == MAX_CSVLOG_OPTS) + return NULL; * An added needless "return" should be removed. *** 2139,2144 **** write_csvlog(ErrorData *edata) --- 2379,2386 ---- write_pipe_chunks(buf.data, buf.len, LOG_DESTINATION_CSVLOG); pfree(buf.data); + + return; } /* -- Itagaki Takahiro -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers