Question

Table:patient
patient_id  varchar(50)
name  varchar(50)
email_id   varchar(50)
country_id  varchar(50)
mobile_no  varchar(20)

Table:Booking
booking_id  varchar(50)
patient_id  varchar(50)
booking_date  date
booking_status varchar(20)   ---- contains the data: Booked, Cancel
booking_type varchar(20)

booking_id  patient_id      booking_date    booking_status  booking_type
2455          111            21-12-2015         Booked       Via mobile
2424          123            21-12-2015         Cancel       Via web
2455          111            21-12-2015         Cancel       Via Web
2455          111            21-12-2015         Cancel       Via mobile

患者将预约并取消与医生的预约。这些将存储在这些表中。预订状态包含预订和取消详细信息的记录。

我们希望计算每位患者的预订数量和超过3个取消的详细信息。

Expected output:
Name    Email_id       Mobile no    Appointment booked  cancelled
san    san@gmail.com    235846               2              7
gow    asas@sfsvs      48645151              1              4
abd    ddscz@fsf        489644               4              5

Answer 1

这称为条件计数。您可以将count（）和sum（）与条件语句一起用作参数以获得预期输出。我正在为下面的sum（）版本提供一个示例：

select p.patient_id, 
       p.email_id, 
       p.mobile_no,
       sum(if(b.booking_status='Booked',1,0)) as AppointmentBooked,
       sum(if(b.booking_status='Cancel',1,0)) as AppointmentCanceled
from patient p left join booking b on p.patient_id=b.patient_id
group by p.patient_id, p.email_id, p.mobile_no
having AppointmentCanceled>3

Answer 2

以下查询也有效。

select p.name,p.email_id,p.mobileno,
SUM(CASE WHEN b.booking_status='Booked' THEN 1 ELSE 0 END) AS bookedcount,
SUM(CASE WHEN b.booking_status='Cancel' THEN 1 ELSE 0 END) AS cancelcount 
from patient p left join booking b
on p.patient_id=b.patient_id group by p.patient_id,p.email_id,p.mobileno      
having cancelcount>3;

查询以计算列数据并显示包含3次以上的结果

2 个答案: