Query optimize

I have following query for find out the total no of counts.


  SELECT count(*)
  FROM contacts_lists
  JOIN plain_contacts ON contacts_lists.contact_id =

plain_contacts.contact_id
JOIN contacts ON contacts.id = plain_contacts.contact_id
WHERE plain_contacts.has_email AND NOT contacts.email_bad AND NOT
contacts.email_unsub AND contacts_lists.list_id = 45897


  It takes 150ms  to complete its task.

Is there any another way to run the above query?
Is there any way to reduce the time? is it possible? please tell
me…

On Apr 18, 9:49am, jey bal [email protected] wrote:

contacts.email_unsub AND contacts_lists.list_id = 45897



It takes 150ms to complete its task.
Is there any another way to run the above query?
Is there any way to reduce the time? is it possible? please tell
me…

well the first step is to run explain against the query and see what
it says. Make sure you’ve added indexes when appropriate (at a minimum
this should include the columns being joined on. You should also index
columns used in the where clause that are sufficiently selective (I’d
guess that contacts_lists.list_id would be a good candidate). use
explain before and after to see the difference adding indexes makes to
the query plan

Fred

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