Help with homework question

[eluser]Unknown[/eluser]
Hi,

Given the following query, how could it be optimized? list all assumptions

Code:

select c.* FROM companies AS c JOIN users AS u USING(companyid) JOIN jobs as J USING(userid) JOIN useraccounts AS ua USING (userid) WHERE j.jobid = 123;

Could anyone give me suggestions as to what can be done?

Thanks,

Jack