mysql | calculate number of days in date range for selected Month - mysql

Question

i have a query. query is all fine. just 1 logical thing remaining taking out the total number of days out of a date range for the selected month..
e-g i have to columns
1 ) project_assign_date //considering as start date
2 ) project_revoke_date // considering as end date
This is my total Query.
SELECT
E.employee_id AS EmployeeID,
ET.employment_id AS EmploymentID,
E.employee_code AS EmployeeCode,
EP.project_id AS ProjectID,
MLP.project_title AS ProjectTitle,
S.base_salary AS EmployeeBaseSalary,
IFNULL(EP.percentCharged, 0) AS PercentCharged,
A.allowance_amount AS EmployeeAllowance,
SUM(IFNULL(A.allowance_amount,0)) + IFNULL(S.base_salary, 0) AS MonthlySalary ,
project_assign_date AS ProjectAssignDate
FROM
(`employee_project` EP)
INNER JOIN `employment` ET
ON `ET`.`employment_id` = `EP`.`employment_id`
AND ET.trashed = 0
AND ET.current = 1
INNER JOIN `employee` E
ON `E`.`employee_id` = `ET`.`employee_id`
AND E.trashed = 0
AND E.enrolled = 1
INNER JOIN `ml_projects` MLP
ON `MLP`.`project_id` = `EP`.`project_id`
AND MLP.trashed = 0
INNER JOIN `salary` S
ON `S`.`employement_id` = `ET`.`employment_id`
AND S.trashed = 0
AND S.status = 2
LEFT JOIN `allowance` A
ON `A`.`employment_id` = `ET`.`employment_id`
AND A.trashed = 0
AND A.status = 2
LEFT JOIN `expense_claims` EC ON EC.employment_id = ET.employment_id AND EC.status = 2
WHERE `EP`.`trashed` = 0
AND EP.current = 1
AND CURRENT_DATE() >= MONTH(project_assign_date)
GROUP BY
E.employee_id,ET.employment_id,EP.project_id
im getting the result fine as showing below.
Array
(
[0] => stdClass Object
(
[EmployeeID] => 1
[EmploymentID] => 15
[EmployeeCode] => E-01
[EmployeeName] => Yasir Khan
[ProjectID] => 1
[ProjectTitle] => Human Resource Management
[ProjectAbbreviation] => HRM
[EmployeeBaseSalary] => 45000.00
[PercentCharged] => 60
[MonthlySalary] => 45000.00
)
[1] => stdClass Object
(
[EmployeeID] => 1
[EmploymentID] => 15
[EmployeeCode] => E-01
[EmployeeName] => Yasir Khan
[ProjectID] => 2
[ProjectTitle] => telenor
[ProjectAbbreviation] => ASD
[EmployeeBaseSalary] => 45000.00
[PercentCharged] => 40
[MonthlySalary] => 45000.00
)
[2] => stdClass Object
(
[EmployeeID] => 9
[EmploymentID] => 20
[EmployeeCode] => E-120
[EmployeeName] => Izhar Ali
[ProjectID] => 1
[ProjectTitle] => Human Resource Management
[ProjectAbbreviation] => HRM
[EmployeeBaseSalary] => 35000.00
[PercentCharged] => 50
[MonthlySalary] => 35000.00
)
[3] => stdClass Object
(
[EmployeeID] => 9
[EmploymentID] => 20
[EmployeeCode] => E-120
[EmployeeName] => Izhar Ali
[ProjectID] => 2
[ProjectTitle] => telenor
[ProjectAbbreviation] => ASD
[EmployeeBaseSalary] => 35000.00
[PercentCharged] => 50
[MonthlySalary] => 35000.00
)
[4] => stdClass Object
(
[EmployeeID] => 19
[EmploymentID] => 32
[EmployeeCode] => E-014
[EmployeeName] => Said Ullah
[ProjectID] => 1
[ProjectTitle] => Human Resource Management
[ProjectAbbreviation] => HRM
[EmployeeBaseSalary] => 20000.00
[PercentCharged] => 100
[MonthlySalary] => 54433.00
)
)
The Important Section starts where i need total number of days project has been assigned to certain employee..
If the whole month do get in the start and end date, then it would be 30 or 31 days but what if project has been assigned to employee in mid of month how would one can calculate total number of days then??