join - increase query performance in mysql -

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i have used query 

select  count(case when c <= 1 1 end) nooffamilieshavingcount1,         count(case when c between 2 , 4 1 end) nooffamilieshavingcountbetween2and4,         count(case when c > 4 1 end) nooffamilieshavingcountgreaterthan3    (   select  count(*) c                user user_id = (select user_id location location_id in(select location_id country state_name='state'))             group house_no         ) t

here sub query returning approximately 10000 records . user table has 10,00,000 records. taking time.then error saying server gone away. using mysql.

i searched google.but no luck me.

what changes need tables.how can execute query increasing query performance.please suggest me.thanks in advance....

try query

select    count(case when c <= 1 1 end) nooffamilieshavingcount1,   count(case when c between 2 , 4 1 end) nooffamilieshavingcountbetween2and4,   count(case when c > 4 1 end) nooffamilieshavingcountgreaterthan3     (select      count(*) c        user u,       location l,      country c         l.state_name='state' ,      l.some_other_column_id= 4 ,  <------- add condition     c.location_id = l.location_id ,      u.user_id = l.user_id    group      u.house_no) t

use proper joins easy understand..

select    count(case when c <= 1 1 end) nooffamilieshavingcount1,   count(case when c between 2 , 4 1 end) nooffamilieshavingcountbetween2and4,   count(case when c > 4 1 end) nooffamilieshavingcountgreaterthan3     (select      count(*) c        user u   inner join       location l   on      l.state_name='state' ,      l.some_other_column_id= 4   <------- add condition     u.user_id = l.user_id    inner join     country c    on      c.location_id = l.location_id    group      u.house_no) t

edited

in cases joins faster sub-queries , rare sub-query faster. accept using subquery more logical , easy understand when comes performance not joins. if using joins db optimize query on own not in case of subquery. try using explain both of query , clear idea how query executes.

hope helps...


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