Identifying queries with nested loops - Amazon Redshift
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Identifying queries with nested loops

The following query identifies queries that have had alert events logged for nested loops. For information on how to fix the nested loop condition, see Nested loop.

select query, trim(querytxt) as SQL, starttime 
from stl_query 
where query in (
select distinct query 
from stl_alert_event_log 
where event like 'Nested Loop Join in the query plan%') 
order by starttime desc;