>Some time ago I changed the pg_stat_temp directory from /var/lib/pgsq/whatever to /tmp
Have you checked the postgres log to see if there are any errors about it not being able to write to the pg_stat_temp dir?
Yep.... no errors =\
And what happens if you run this query?
SELECT idstat.schemaname AS schema, idstat.relname AS table_name, indexrelname AS index_name, idstat.idx_scan AS times_used, pg_size_pretty(pg_relation_size(quote_ident(idstat.schemaname) || '.' || quote_ident(idstat.relname))) AS table_size, pg_size_pretty(pg_relation_size(quote_ident(idstat.schemaname) || '.' || quote_ident(indexrelname))) AS index_size, n_tup_upd + n_tup_ins + n_tup_del as num_writes, indexdef AS definition FROM pg_stat_user_indexes AS idstat JOIN pg_indexes ON indexrelname = indexname JOIN pg_stat_user_tables AS tabstat ON idstat.relname = tabstat.relname WHERE indexrelname = ' {YOUR QUERY NAME } ';
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Melvin Davidson I reserve the right to fantasize. Whether or not you wish to share my fantasy is entirely up to you.