2009/11/25 Pavel Stehule <pavel.steh...@gmail.com>: > 2009/11/25 Daniel Farina <drfar...@gmail.com>: >> On Tue, Nov 24, 2009 at 10:23 PM, Jeff Davis <pg...@j-davis.com> wrote: >>> On Wed, 2009-11-25 at 06:35 +0100, Pavel Stehule wrote: >>>> I believe so using an "internal" minimalize necessary changes in COPY >>>> implementation. Using a funcapi needs more work inside COPY - you >>>> have to take some functionality from COPY to stream functions. >>>> Probably the most slow operations is parsing - calling a input >>>> functions. This is called once every where. Second slow operation is >>>> reading from network - it is same. So I don't see too much reasons, >>>> why non internal implementation have to be significant slower than >>>> your actual implementation. I am sure, so it needs more work. >>> >>> I apologize, but I don't understand what you're saying. Can you please >>> restate with some examples? >>> >>> It seems like you're advocating that we move records from a table into a >>> function using COPY. But that's not what COPY normally does: COPY >>> normally translates records to bytes or bytes to records. >> >> Perhaps what we want is pluggable transformation functions that can >> format the row any way that is desired, with the current behavior >> being some default. Putting COPY TO FUNCTION as submitted aside, what >> about something like this: >> >> COPY foo TO '/tmp/foo' USING postgres_builtin_formatter(csv = true); >> >> This is something completely different than what was submitted, so in >> some aspect: >> >> COPY foo TO FUNCTION dblink_send_row USING >> postgres_builtin_formatter(binary = true); >> >> Would compose the two features... >> > > yes - it is two features - and should be solved independently
it and it is not (some thinking) - smarter streams should to accept/returns tuples. Formating function has sense for text output - there are input/output formating (text based/bytea based) functions. I see one possible problem - when formater functions will be row based - then you cannot generate some prolog and epilog part of file - (xml). Pavel > > Pavel > >> (Again, very, very far from a real syntax suggestion) >> >> fdr >> >> -- >> Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) >> To make changes to your subscription: >> http://www.postgresql.org/mailpref/pgsql-hackers >> > -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
