Kelly Burkhart wrote:
On 1/4/06, Steve Eckmann
<eckmann@xxxxxxxxxxxx>
wrote:
Thanks,
Steinar. I don't think we would really run with fsync off, but
I need to document the performance tradeoffs. You're right that my
explanation was confusing; probably because I'm confused about how to
use COPY! I could batch multiple INSERTS using COPY statements, I just
don't see how to do it without adding another process to read from
STDIN, since the application that is currently the database client is
constructing rows on the fly. I would need to get those rows into some
process's STDIN stream or into a server-side file before COPY could be
used, right?
Steve,
You can use copy without resorting to another process. See the
libpq documentation for 'Functions Associated with the copy
Command". We do something like this:
char *mbuf;
// allocate space and fill mbuf with appropriately formatted data
somehow
PQexec( conn, "begin" );
PQexec( conn, "copy mytable from stdin" );
PQputCopyData( conn, mbuf, strlen(mbuf) );
PQputCopyEnd( conn, NULL );
PQexec( conn, "commit" );
-K
Thanks for the concrete example, Kelly. I had read the relevant libpq
doc but didn't put the pieces together.
Regards, Steve
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