Hi, I'm catching up with the discussion as a reviewer...
(2013/08/27 5:35), Tom Lane wrote: > Andres Freund <and...@2ndquadrant.com> writes: >> On 2013-08-26 10:10:54 -0700, Josh Berkus wrote: >>> I'm going to reverse my vote, and vote against this patch. The reason >>> why is that I think we should instead have a function: >>> >>> pg_controldata(parameter text) >>> >>> ... which would report *all* strings in pg_controldata. Hence, you'd do >>> instead: >>> >>> pg_controldata('system identifier') >>> >>> This will hopefully spare us from 15 patches incrementally adding all of >>> the individual items in controldata. > >> If anything but the proposed feature, it should be an SRF - passing in >> text parameters isn't very discoverable. > > I'm not pleased with the idea that we'd have to dumb all the relevant > datatypes down to text so that we could push them through this single > function. > > Also, what about i18n? pg_controldata localizes all the strings it > prints, but I doubt that's a great idea for either the input or the > output of this proposed function. How about adding new system view with new function which returns a single pg_controldata value in text type, and using a cast for each column in the view definition? CREATE VIEW pg_catalog.pg_controldata AS SELECT pg_controldata('control_version')::integer AS control_version, pg_controldata('catalog_version')::integer AS catalog_version, pg_controldata('system_identifier')::bigint AS system_identifier, ... pg_controldata('next_xlog_file')::char(25) AS next_xlog_file, ... pg_controldata('encoding')::text AS encoding; Given that the view can work like a SRF, and it allows us to retrieve all the values of pg_controldata with appropriate types in single record from the view: select * from pg_catalog.pg_controldata; To get the system identifier value: select system_identifier from pg_catalog.pg_controldata; Regards, -- Satoshi Nagayasu <sn...@uptime.jp> Uptime Technologies, LLC. http://www.uptime.jp -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers