Need help to understand select_scan

Hi Guys,

I am new to MySQL and i have to analyze and reduce the value of select_scan status variable for a large web application. but i don’t have a deep knowledge about these select_scan.

i just know that it is incremented whenever a full table scan is done on the first table used in a join. But i am not sure about how can i reduce this and what can be an acceptable value for a large application. Currently it averages to 43000 per day.

The application uses Hibernate and all the queries are generated by hibernate.

Can anyone kindly explain these select_scan to me and help me out that how to reduce the number. will indexing be of any help for this.

any help will be appreciated deeply.

regards,

Nasir Rafiq