Mysql Query Optimization - Shared Query need to optimized - mysql

Question

Please help me to optimize below Query -
SELECT DISTINCT
al.displayName AS 'Brand',
al.locationName AS 'Campus',
pg.groupName AS 'School Phase',
result.programName AS 'Grade',
pc.categoryName AS 'Grade Category',
result.batchName AS 'Intake',
result.periodName AS 'Period',
admission.id AS 'ADmission',
result.stdName AS 'Student Name',
usr.code AS 'Student Id',
result.courseName AS 'Subject',
result.courseVariant AS 'Subject Variant',
cc.categoryName AS 'Subject Category',
fac.printName AS 'Teacher',
result.planPrintName AS 'Scheme',
planRank.marksObtainedFrom AS 'Maximum Marks',
planRank.gradeObtainedFrom AS 'Maximum Grade',
planRank.obtainedMarks AS 'Subject Level Marks',
planRank.grade AS 'Subject Grade',
planRank.obtainedMarks AS 'Percentage',
planRank.status AS 'Result Status',
result.levelOnePrintName AS 'Type',
typeRank.effectiveMarks AS 'Type Marks',
typeRank.grade AS 'Type Grade',
typeRank.status AS 'Type Result Status',
result.levelTwoPrintName AS 'Sub Type',
subTypeRank.effectiveMarks AS 'Sub Type Marks',
subTypeRank.grade AS 'Sub Type Grade',
subTypeRank.status AS 'Sub Type Result Status',
result.levelThreePrintName AS 'Method',
result.effectiveMarks AS 'Method Marks',
result.grade AS 'Method Grade',
result.status AS 'Method Result Status',
CASE
WHEN evntDetail.eventName IS NULL THEN evnt.detailSequenceNumber
WHEN evntDetail.eventName IS NOT NULL THEN evntDetail.eventName
ELSE NULL
END AS 'Event',
eventMarks.effectiveMarks AS 'Event Marks',
eventMarks.finalGrade AS 'Event Grade'
FROM
marksheet AS result
INNER JOIN
admission AS admission ON admission.id = result.admissionId
INNER JOIN
users AS usr ON usr.id = result.studentId
INNER JOIN
academy_location AS al ON al.id = admission.academyLocationId
INNER JOIN
programs AS prgm ON prgm.id = result.programId
LEFT OUTER JOIN
program_group AS pg ON pg.id = prgm.programGroupId
LEFT OUTER JOIN
program_category AS pc ON pc.id = prgm.programCategoryId
LEFT OUTER JOIN
courses AS course ON course.id = result.courseId
LEFT OUTER JOIN
course_category AS cc ON cc.id = course.courseCategoryId
LEFT OUTER JOIN
program_batch_course_param AS param ON result.courseVariantId = param.courseVarientId
AND result.periodId = param.progBatchPeriodConfigId
LEFT OUTER JOIN
prog_batch_course_faculty AS pbcf ON pbcf.progBatchCourseParamId = param.id
LEFT OUTER JOIN
users AS fac ON fac.id = pbcf.facultyId
LEFT OUTER JOIN
evaluation_plan_rank AS planRank ON result.admissionId = planRank.admissionId
AND (result.courseVariantId = planRank.courseVariantId
OR planRank.courseVariantId IS NULL)
AND result.sectionId = planRank.sectionId
AND result.periodId = planRank.periodId
AND result.evaluationPlanId = planRank.evaluationPlanId
LEFT OUTER JOIN
evaluation_plan_level_one_rank AS typeRank ON result.admissionId = typeRank.admissionId
AND (result.courseVariantId = typeRank.courseVariantId
OR typeRank.courseVariantId IS NULL)
AND result.periodId = typeRank.periodId
AND result.sectionId = typeRank.sectionId
AND result.evaluationPlanLevelOneId = typeRank.evaluationPlanLevelOneId
LEFT OUTER JOIN
evaluation_plan_level_two_rank AS subTypeRank ON result.admissionId = subTypeRank.admissionId
AND (result.courseVariantId = subTypeRank.courseVariantId)
AND result.periodId = subTypeRank.periodId
AND result.sectionId = subTypeRank.sectionId
AND result.evaluationPlanLevelTwoId = subTypeRank.evaluationPlanLevelTwoId
INNER JOIN
eval_seq_detail AS evnt ON result.evaluationPlanThreeId = evnt.evalSequenceId
LEFT OUTER JOIN
examination_result AS eventMarks ON result.admissionId = eventMarks.admissionId
AND (result.courseVariantId = eventMarks.courseVariantId
OR eventMarks.courseVariantId IS NULL)
AND result.sectionId = eventMarks.sectionId
AND result.periodId = eventMarks.periodId
AND evnt.id = eventMarks.evaluationDetailSequenceId
LEFT OUTER JOIN
evaluation_type_course typeCourse ON eventMarks.courseVariantId = typeCourse.courseVariantId
AND eventMarks.periodId = typeCourse.periodId
LEFT OUTER JOIN
exam_event_detail evntDetail ON eventMarks.evaluationDetailSequenceId = evntDetail.eventId
AND evntDetail.evaluationTypeCourseId = typeCourse.id
WHERE
eventMarks.examResultStatus IS NOT NULL
AND result.evaluationPlanId IS NOT NULL
AND result.evaluationPlanLevelOneId IS NOT NULL
AND result.evaluationPlanLevelTwoId IS NOT NULL
AND result.evaluationPlanThreeId IS NOT NULL;
In tables marksheet = '740119' and examination_result = '4891575' approx records.
when I execute query then it will take around 10 min and also show time out error, as data-set is large.
I applied indexes on table's for performance but still Query take lots of time.
I applied Explain on Query to check status -

Answer 1

Add the keyword "STRAIGHT_JOIN" to you query. It looks like you have everything in proper logical alignment. You are querying from the main table and joining to all the lookup tables secondary. MySQL sometimes tries to optimize based on table row sizes and will look at a smaller table as a more beneficial path and can choke.
SELECT STRAIGHT_JOIN (rest of query)
Tells MySQL to do the query in the order you provided, don't think for me.
Now, that said, you don't really have a WHERE clause that may be taking advantage of an index. To prevent the need of having to go to every data page for the records, if you have an index on the where clauses, the engine can pre-qualify those records where not null via the index. Assuming that each evaluation plan is an integer (numeric) based "ID" value, I would add an index on
( evaluationPlanId, evaluationPlanLevelOneId, evaluationPlanLevelTwoId, evaluationPlanThreeId )