distinct clause issue for 600000 records

[Rami Nalamalpu]

Hi,

I am facing issue with distinct clause whenever i am trying to retrieve 600000 records using one of the tool(pdi-etl tool),here issue is with CPU usage up to 100% .

As per my DBA input, the root cause for my issue is DISTINCT , i kept distinct clause in my select query because of getting duplicate records even though i have unique data. actually i should not get duplicate data why because i have all records with columns are unique.

Due to this distinct i am reaching CPU usage upto 100% how can i avoid duplicate records in MySQL database.

below is my sample query, when i join with other table then i am getting duplicate records but i have only one record.

select ee.id
from extn ee
left join srl prd on prd.id =ee.id where ee.id=2662

Thank you