mysql - What is the best way to optimize this sql query -


i have following sql query, noticed it's putting pressure on server since every time run it, cpu usage jumps 20%. 

select      c.name, c.billingaddress, c.billingcity, c.billingstate, c.billingzip,c.ifactive,     (select count(l.id) newloads l l.idcompany = c.id , l.smallstatus='1') numberloads,     (select (sum(l.loadrate))/(sum(l.esmiles)) newloads l l.idcompany = c.id , l.loadrate != '0' , l.esmiles != '0' , l.smallstatus='1') rpm     `companies` c ifcontractor ='0' $cond     order numberloads desc

this might more efficient:

select  c.name, c.billingaddress, c.billingcity,         c.billingstate, c.billingzip, c.ifactive,         x.numberloads, x.rpm             ( select  l.idcompany,                 count(*) numberloads,                 sum(l.loadrate))/(sum(l.esmiles) rpm              newloads l              l.smallstatus = '1'        ) x     join  companies c  on c.id = x.idcompany      ifcontractor = '0' $cond     order  x.numberloads desc;

please provide show create table , explain select ....


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