我很确定这与我选择表或联接的顺序有关,但是在我的查询中尝试了各种重新排序后,我仍然遇到 0 个结果。
有人能指出我正确的方向吗?
附件 A(返回 355 个结果):
SELECT DISTINCT
person.person_id as "Person ID",
CONCAT(person.last, ', ', person.first) as "Patient Name",
person.birthday as "Birthday",
person_ins_tie.insurance_id as "Insurance ID",
insurance.carrier as "Carrier",
insurance.phone as "Carrier Phone Number"
FROM
person
JOIN
person_ins_tie ON person.person_id = person_ins_tie.person_id
JOIN
insurance ON person_ins_tie.insurance_id = insurance.insurance_id
WHERE
insurance.carrier LIKE 'Blue%'
附件 B(返回 0 个结果/无错误):
SELECT DISTINCT
person.person_id as 'Person ID',
patient.display_id as 'Chart #',
CONCAT(person.last, ', ', person.first) as 'Patient Name',
person.birthday as 'Birthday',
insurance.insurance_id as 'Insurance ID',
insurance.carrier as 'Carrier',
insurance.phone as 'Carrier Phone Number'
FROM
person
JOIN
person_ins_tie ON person.person_id = person_ins_tie.person_id
JOIN
insurance ON person_ins_tie.insurance_id = insurance.insurance_id
JOIN
patient ON person.person_id = patient.person_id
WHERE
insurance.carrier LIKE 'Blue%'
感谢您的反馈!
最佳答案
JOIN
表示INNER JOIN
。
在这种情况下,当您加入 patent
表时,它会尝试从 person
表中的 person_id
中查找 person_id
patent
表的 >。因此,这里唯一的可能性是在 patent
表的 person_id
列中找不到前一个连接集中的 person_id
。共有 0 条记录!
关于MySQL JOIN - 没有结果,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/22391130/