MySQL - optimize query with a sub-query - mysql

Question

I am currently bit stuck at the query which needs a bit of optimization - I am looking for a way how to optimize (if possible) following query (I have no idea what to do here at the moment :/):
SELECT count(distinct(pj.id)) as qty
FROM `project_jobs` `pj`
JOIN `projects` `p` ON pj.project_id = p.id AND p.status NOT IN ("CANCELED","DELETED","ARCHIVED")
WHERE
(
(
(pj.job_type_service_id IN (SELECT id FROM job_type_services WHERE job_type_id IN (4,2,3)))
AND
(pj.new_status_id IN ("wip","completed","delivered"))
)
AND (pj.status<>'DELETED' AND pj.status<>'CANCELED')
)
AND
(pj.due_date >= '2010-04-01 00:00:00' AND pj.due_date <= '2018-05-09 23:59:59')
and exists
(SELECT * FROM project_job_parents pjp
WHERE pjp.project_job_id IN
(SELECT id FROM project_jobs WHERE job_type_id IN (1,24,7,8,32,34,33))
and
pjp.parent_id = pj.id
)
EXPLAIN gives following info:
Is there anything what can be done here to optimize and speed up the query?

Answer 1

EXISTS subqueries usually perform significantly better than IN subqueries, at least in most MySQL versions (transformed the query below).
You didn't provide the tables structure, so it will be hard to tell which indexes exist and which columns they contain. So, I'll just specify which indexes you should have.
Indexes to add:
ALTER TABLE `job_type_services` ADD INDEX `job_type_services_idx_id_id` (`job_type_id`,`id`);
ALTER TABLE `project_job_parents` ADD INDEX `project_job_parents_idx_id` (`parent_id`);
ALTER TABLE `project_job_parents` ADD INDEX `project_job_parents_idx_id` (`project_job_id`);
ALTER TABLE `project_jobs` ADD INDEX `project_jobs_idx_id_id_status_id` (`new_status_id`,`project_id`,`status`,`id`);
ALTER TABLE `project_jobs` ADD INDEX `project_jobs_idx_id` (`job_type_service_id`);
ALTER TABLE `project_jobs` ADD INDEX `project_jobs_idx_id` (`id`);
ALTER TABLE `project_jobs` ADD INDEX `project_jobs_idx_id_id` (`job_type_id`,`id`);
ALTER TABLE `projects` ADD INDEX `projects_idx_status_id` (`status`,`id`);
Transformed query:
SELECT
count(DISTINCT (`pj`.id)) AS qty
FROM
`project_jobs` `pj`
JOIN
`projects` `p`
ON `pj`.project_id = `p`.id
AND `p`.status NOT IN (
'CANCELED',
'DELETED',
'ARCHIVED')
WHERE
(
(
(
EXISTS (
SELECT
1
FROM
job_type_services
WHERE
job_type_services.job_type_id IN (
4, 2, 3
)
AND `pj`.job_type_service_id = job_type_services.id
)
)
AND (
`pj`.new_status_id IN (
'wip', 'completed', 'delivered'
)
)
)
AND (
`pj`.status <> 'DELETED'
AND `pj`.status <> 'CANCELED'
)
)
AND (
`pj`.due_date >= '2010-04-01 00:00:00'
AND `pj`.due_date <= '2018-05-09 23:59:59'
)
AND EXISTS (
SELECT
*
FROM
project_job_parents pjp
WHERE
EXISTS (
SELECT
1
FROM
project_jobs
WHERE
project_jobs.job_type_id IN (
1, 24, 7, 8, 32, 34, 33
)
AND pjp.project_job_id = project_jobs.id
)
AND pjp.parent_id = `pj`.id
)