SELECT n.nspname as schema, i.relname as table, i.indexrelname as index, i.idx_scan, i.idx_tup_read, i.idx_tup_fetch, CASE WHEN idx.indisprimary THEN 'pkey' WHEN idx.indisunique THEN 'uidx' ELSE 'idx' END AS type, pg_get_indexdef(idx.indexrelid), CASE WHEN idx.indisvalid THEN 'valid' ELSE 'INVALID' END as statusi, pg_relation_size(quote_ident(n.nspname)|| '.' || quote_ident(i.relname)) as size_in_bytes, pg_size_pretty(pg_relation_size(quote_ident(n.nspname)|| '.' || quote_ident(i.relname))) as size FROM pg_stat_all_indexes i JOIN pg_class c ON (c.oid = i.relid) JOIN pg_namespace n ON (n.oid = c.relnamespace) JOIN pg_index idx ON (idx.indexrelid = i.indexrelid ) WHERE n.nspname NOT LIKE 'pg_%' ORDER BY 1, 2, 3;
I've found more then 100 indexes that the columns:
"idx_scan", "idx_tup_read" and "idx_tup_fetch" are 0.
So, it's safe to say that they are not being used, is that right?
But some indexes have almost 100GB on the size column. This means they are not being used now, but they could be used in the past?
Index size and index usage are unrelated. Modifications to the index to keep it in sync with the table do not count as "usage" - only reading it for where clause use counts.
