Add 'PostgreSQL/description/index_usage_by_scans.sql'

PostgreSQL/description/index_usage_by_scans.sql

@@ -0,0 +1,19 @@
+SELECT
+    t.schemaname,
+    t.tablename,
+    c.reltuples::bigint                            AS num_rows,
+    pg_size_pretty(pg_relation_size(c.oid))        AS table_size,
+    psai.indexrelname                              AS index_name,
+    pg_size_pretty(pg_relation_size(i.indexrelid)) AS index_size,
+    CASE WHEN i.indisunique THEN 'Y' ELSE 'N' END  AS "unique",
+    psai.idx_scan                                  AS number_of_scans,
+    psai.idx_tup_read                              AS tuples_read,
+    psai.idx_tup_fetch                             AS tuples_fetched
+FROM
+    pg_tables t
+    LEFT JOIN pg_class c ON t.tablename = c.relname
+    LEFT JOIN pg_index i ON c.oid = i.indrelid
+    LEFT JOIN pg_stat_all_indexes psai ON i.indexrelid = psai.indexrelid
+WHERE
+    t.schemaname NOT IN ('pg_catalog', 'information_schema')
+ORDER BY psai.idx_scan DESC;