[Postgres] Spot a missing postgreSQL index

–tuto tuning psql
–Spot a missing PostgreSQL index

–returns the tables which have been hit by sequential scans the most and tells us how many rows a sequential scan has hit on average.
SELECT schemaname, 
              relname, 
              seq_scan, 
              seq_tup_read, 
              idx_scan, 
              seq_tup_read / seq_scan AS avg
 FROM         pg_stat_user_tables 
 WHERE        seq_scan > 0 
 ORDER BY     seq_tup_read DESC;

–Finding slow queries to be executed on pgadmin
SELECT query, 
              total_exec_time, 
              calls, 
              mean_exec_time 
       FROM   pg_stat_statements 
       ORDER BY total_exec_time DESC;