SQL query optimization for MySql database - php

Question

I have 3 table: user , company and deal.
One user may own several companies. Deal is made between the 2 companies. I need a list of deals, which involved my company.
Deals must contain the following fields: partner_company_id,my_company_id,partner_photo,partner_name,deal_about.
Language code: PHP.
Database: Mysql.
1.List of my company I can get by user ID.
user_id = 22;
companyList = query('SELECT company_id FROM company WHERE user_id = ?', user_id);
2. Then i get deal list where my_company_id is company_first_id
list1 = query('SELECT u.name AS partner_name, u.photo AS partner_photo, d.first_company_id AS
my_company_id , d.second_company_id AS partner_company_id,d.about AS deal_about FROM deal AS d
INNER JOIN company AS c ON c.company_id = d.second_company_id
INNER JOIN user AS u ON u.user_ud = c.user_id
WHERE d.company_first_id IN (?)', companyList);
3. Then i get deal list where my_company_id is company_second_id
list2 = query('SELECT u.name AS partner_name, u.photo AS partner_photo, d.first_company_id AS
partner_company_id , d.second_company_id AS my_company_id,d.about AS deal_about FROM deal AS d
INNER JOIN company AS c ON c.company_id = d.first_company_id
INNER JOIN user AS u ON u.user_ud = c.user_id
WHERE d.company_second_id IN (?)', companyList);
4. then i marge to array and set limit list
list = array_marge(list1,list2);
result = array_slice (list ,0 , 10);
HELP please optimize this queries.
THANKS.
DATABASE SCHEME
user | company | deal |
--------------------------------------------------
user_d | company_id | deal_id
photo | user_id |first_company_id
name | about |second_company_id
| |description

Answer 1

Are your queries so slow? They don't look slow (provided you have indexes on all IDs of course).
However, you can save one database access by combining the two deal queries. Either you simply select query1 UNION ALL query1 or you do it in one pass:
select
u.name AS partner_name,
u.photo AS partner_photo,
d.my_company_id,
d.partner_company_id,
d.about AS deal_about
from
(
select
about,
case when company_first_id in (?) then
company_first_id
else
company_second_id
end as my_company_id,
case when company_first_id in (?) then
company_second_id
else
company_first_id
end as partner_company_id
from deal
where company_first_id in (?) OR d.company_second_id in (?)
) as d
inner join company as c on c.company_id = d.partner_company_id
inner join user as u on u.user_ud = c.user_id