MYSQL | Getting syntax error for using subquery in COUNT() - mysql

Question

SELECT
E.`employee_id`,
E.`full_name`,
LE.`no_of_leaves` AS AllocatedLeaves,
MLLT.`leave_type` AS LeaveTypeName,
COUNT(SELECT * FROM leave_approval WHERE employee_id = 1) AS TotalLeavesTaken
FROM employee E
INNER JOIN leave_entitlement LE
ON E.`employee_id` = LE.`employee_id`
INNER JOIN `ml_leave_type` MLLT
ON MLLT.`ml_leave_type_id` = LE.`ml_leave_type_id`
LEFT JOIN leave_approval LA
ON E.`employee_id` = LA.`employee_id`
LEFT JOIN leave_application LAPP
ON LAPP.`application_id` = LA.`leave_application_id`
LEFT JOIN ml_leave_type MLLTLA
ON MLLTLA.`ml_leave_type_id` = LAPP.`ml_leave_type_id`
i am getting syntax error near count, but i tried to find out the syntax error and i could not find any?
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'select * from leave_approval where employee_id = 1) AS TotalLeavesTaken
from emp' at line 6
Is it really a syntax error. or is there something i am missing here??

Answer 1

This line:
COUNT(SELECT * FROM leave_approval WHERE employee_id = 1) AS TotalLeavesTaken
is incorrect. You can not do a count on select * subquery without placing it in parentheses, but even then you'd need a group by and additional logic. The better approach would be:
(Select count(*) from leave_approval where employee_id = 1) AS TotalLeavesTaken

Answer 2

change
COUNT(SELECT * FROM leave_approval WHERE employee_id = 1) AS TotalLeavesTaken
to
(SELECT count(*) FROM leave_approval WHERE employee_id = 1) AS TotalLeavesTaken

Answer 3

No need to use subquery for count in your case check below query
Try this:
SELECT E.employee_id, E.full_name, LE.no_of_leaves AS AllocatedLeaves,
MLLT.leave_type AS LeaveTypeName,
SUM(CASE WHEN LA.employee_id = 1 THEN 1 ELSE 0 END) AS TotalLeavesTakenByEmplyeeNo1
FROM employee E
INNER JOIN leave_entitlement LE ON E.employee_id = LE.employee_id
INNER JOIN `ml_leave_type` MLLT ON MLLT.ml_leave_type_id = LE.ml_leave_type_id
LEFT JOIN leave_approval LA ON E.employee_id = LA.employee_id
LEFT JOIN leave_application LAPP ON LAPP.application_id = LA.leave_application_id
LEFT JOIN ml_leave_type MLLTLA ON MLLTLA.ml_leave_type_id = LAPP.ml_leave_type_id
GROUP BY E.employee_id;

Answer 4

Try This Query
SELECT E.`employee_id`,E.`full_name`,LE.`no_of_leaves` AS AllocatedLeaves,MLLT.`leave_type` AS LeaveTypeName,
SUM( CASE WHEN LA.employee_id = '1' THEN 1 ELSE 0 END ) as TotalLeavesTaken
FROM employee E
INNER JOIN leave_entitlement LE
ON E.`employee_id` = LE.`employee_id`
INNER JOIN `ml_leave_type` MLLT
ON MLLT.`ml_leave_type_id` = LE.`ml_leave_type_id`
LEFT JOIN leave_approval LA
ON E.`employee_id` = LA.`employee_id`
LEFT JOIN leave_application LAPP
ON LAPP.`application_id` = LA.`leave_application_id`
LEFT JOIN ml_leave_type MLLTLA
ON MLLTLA.`ml_leave_type_id` = LAPP.`ml_leave_type_id`
Only you have to replace COUNT(SELECT * FROM leave_approval WHERE employee_id = 1) to SUM( CASE WHEN LA.employee_id = '1' THEN 1 ELSE 0 END )
Thanks it, Try this because i have tried this query and it will give you perfect result