考虑以下 mysql 语句:
SELECT costs.cost AS package, payments.cost AS labs, patients.fname, patients.lname, patients.sname, visit.id AS visitid, patients.id, pharm_payments.cost AS pharm_costs ,costs.cost+payments.cost+pharm_payments.cost AS total_cost ,
CASE pharm_payments.cost WHEN pharm_payments.visitid=visit.id THEN pharm_payments.cost
WHEN pharm_payments.visitid != visit.id THEN 0
CASE costs.cost WHEN cost.visitid=visit.id THEN costs.cost
WHEN costs.visitid != visit.id THEN 0
FROM costs
LEFT JOIN visit ON costs.visitid = visit.id
LEFT JOIN patients ON visit.patientid = patients.id
LEFT JOIN pharm_payments ON pharm_payments.visitid = visit.id
LEFT JOIN payments ON payments.visitid = visit.id
WHERE costs.paid = 'not paid'
AND visit.VisitDate >= CURDATE( )
LIMIT 0 , 30
查询的预期结果应该是访问 id 不同的地方,它应该返回零值。我不断收到以下错误:
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 'CASE costs.cost WHEN cost.visitid=visit.id THEN costs.cost WHEN costs.visitid !=' at line 4
我该如何解决这个错误?