联合查询出错数据对不上,数据字段莫名被置空了,求解惑

问题遇到的现象和发生背景

对两张表进行关联查询的时候出现了数据不一致的问题,排查后发现是自己设计的字段被置空了

问题相关代码,请勿粘贴截图

SELECT a.id, a.doctor_name, b.doctor_grade, b.doctor_edu, a.doctor_url, a.doctor_hash, a.recovery_data, a.manner_data, a.online_check, a.appoint_register, a.faculty_name, b.faculty_direction, b.hospital_name, a.city_name, b.total_visit, b.yesterday_visit, b.total_page, b.total_patient, b.after_patient, b.after_judge, b.thank_note, b.gift, b.on_line, b.open_time, b.create_time FROM web_haodaifu_doctor_list AS a LEFT JOIN web_haodaifu_doctor_details AS b ON (a.doctor_hash = b.doctor_hash and b.create_time >'2022-08-08 00:00:00' and b.create_time < '2022-08-08 23:59:59') -- 查询有1474条

SELECT COUNT(*) FROM web_haodaifu_doctor_details WHERE create_time >'2022-08-08 00:00:00' and create_time < '2022-08-08 23:59:59'
-- 查询有334条

运行结果及报错内容

正常情况下两个sql查询的数据条数是一样的,但是第一条查询对1000多条,主要是b.create_time = null了

我的解答思路和尝试过的方法

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已解决,对create_time添加where来限制