For the record: On Wed, Feb 09, 2011 at 11:12:01PM +0100, Karsten Hilbert wrote: > Attached find some table and view definitions from the > GNUmed (www.gnumed.de) database. > > Unfortunately I do not understand why PostgreSQL says > > psql:xx.sql:14: ERROR: could not implement UNION > DETAIL: Some of the datatypes only support hashing, while others only support sorting. The solution lies in these bits: > View "dem.v_message_inbox" > Column | Type | Modifiers > --------------------+--------------------------+----------- > received_when | timestamp with time zone | > provider | text | > importance | integer | > category | text | > l10n_category | text | > type | text | > l10n_type | text | > comment | text | > pk_context | integer[] | This data type can only be hashed. > data | text | > pk_inbox_message | integer | > pk_staff | integer | > pk_category | integer | > pk_type | integer | > pk_patient | integer | > is_virtual | boolean | > xmin_message_inbox | xid | This data type can only be sorted. By defining an explicit caster: create or replace function gm.xid2int(xid) returns integer language 'sql' as 'select $1::text::integer;'; and applying that to the XMIN column inside the view definition nicely solves the "could not implement UNION". Karsten -- GPG key ID E4071346 @ gpg-keyserver.de E167 67FD A291 2BEA 73BD 4537 78B9 A9F9 E407 1346 -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
