Tables:
Doctor(doctor_id, name, address, tel, specialty)
Patient(patient_id, name, numsecu, doctor_reference)
Visit(doctor, patient, date_visit)
The question is show the patients who have seen every specialty doctors.
I do this way but I don't know how to check that the patients have seen every specialty doctors.
select distinct p.nom, m.specialite
from patient p, visite v, medecin m
where p.patient_id = v.patient
and v.medecin = m.medecin_id
group by p.nom, m.specialite
Made a bit of an assumption here that "specialty doctors" are identified by a non-null specialite column in the medecin table.
EDIT: Added JOIN to medecin in the main query to filter the visits to only specialty doctors.
SELECT p.nom
FROM patient p
INNER JOIN visite v
ON p.patient_id = v.patient
INNER JOIN medicin m
ON v.medecin = m.medecin_id
WHERE m.specialite IS NOT NULL
GROUP BY p.nom
HAVING COUNT(DISTINCT m.medecin_id) = (SELECT COUNT(*)
FROM medecin
WHERE specialite IS NOT NULL)
Related
I need to get the surnames of bosses who manage at least two employees from the query below that earn no more than twice the average earnings of ALL people they direct.
I'm stuck here:
SELECT surname from emp k INNER JOIN
(SELECT surname, base_salary
from emp p LEFT JOIN
(select id_team, avg(base_salary) as s, count(*) as c from emp group by id_team)
as o ON(p.id_team = o.id_team)
where p.base_salary between o.s*0.7 and o.s*1.3 and o.c >=2) l ON (k.id_boss = o.id_boss)
having count(k.id_boss) >2 ??? AND k.base_salary < ????
I hope you get my point. Any advices how could I do that?
Here's what the full table looks like:
Based on your query you should just add the proper having clause
having count(k.id_boss) >2 AND k.base_salary < 2*l.s
SELECT k.surname
from emp k
INNER JOIN (
SELECT surname, base_salary, id_boss
from emp p
LEFT JOIN (
select id_team, avg(base_salary) as s, count(*) as c
from emp
group by id_team
) o ON p.id_team = o.id_team
where p.base_salary between o.s*0.7 and o.s*1.3 and o.c >=2
) l ON k.id_boss = o.id_boss
group by k.surname
having count(l.id_boss) >2
AND k.base_salary < 2*l.s
Using SQL, my job is to fetch the SSN of students who enrolled in a course without enrolling in that course’s prerequisite(s). I'm using Access. The tables I need are as follows:
STUDENT (SSN, SNAME, MAJOR, DOB, ADDRESS)
ENROLLED (SSN, CID, GRADE)
PREQ (CID, PREQCID, PASSINGGRADE, NOTE)
Here's what I've done so far.
select *
from
(select SSN, CID from ENROLLED) AS enrolled
left join
(select CID, PREQCID FROM PREQ) AS prereq ON enrolled.CID = prereq.CID;
What I'm missing is how to check each row of the same student on the condition WHERE enrolled.CID = prereq.CID for a PREQCID that's NOT in enrolled.CID.
Is what I'm asking for here a loop? Am I on the right track? Please keep in mind this I'm in an introductory course so the simplest of solutions is preferable.
Here's another way using not exists:
select e1.ssn
from enrolled e1 left join preq p on e1.cid = p.cid
where
p.preqcid is not null and
not exists (select 1 from enrolled e2 where e2.ssn = e1.ssn and e2.cid = p.preqcid)
This is essentially stating:
"Select the ssn for all enrollments where there is a prerequisite course and the prerequisite course ID does not exist in the table of enrollments for that ssn."
I use select 1 purely for optimisation - we don't care about the values held by the nested query, only whether or not the nested query returns one or more records.
You could also write this using joins as:
select e1.ssn
from
(
enrolled e1 left join preq p on e1.cid = p.cid
)
left join enrolled e2 on
p.preqcid = e2.cid and e1.ssn = e2.ssn
where
e2.cid is null
Here, the enrolled table is referenced twice: the first is left joined on the table of prerequisite courses for each course, and the second is left joined on the prerequisite course ID and the ssn from the original enrollment.
The where clause then causes records to be selected for which the link on the prerequisite course is null for the given ssn.
I'm sure there is a cleaner way to do this, but this gets you your result:
Select S.SSN, E.CID From Student S
Inner Join Enrolled E on E.SSN = S.SSN
Where E.CID IN (Select CID From PREQ Where Preqcid NOT IN
(Select CID From Enbrolled Where SSN = S.SSN))
This might work if analytic functions and CTEs are available:
with d as (
select ssn, cid,
count(distinct p.cid) over (partition by e.ssn, e.cid) ecnt, ,
count(distinct e.cid) over (partition by e.ssn, p.cid) pcnt
from enrolled e left outer join preq p on p.cid = e.cid
)
select distinct ssn, cid from d
where ecnt = pcnt;
Using this relational schema, patient ID and staff ID are foreign keys with id.staff and pid.patient being unique keys:
staff(ID, fname, lname, role)
patient(pID, pFname, pLname, bdate, address, phone)
appointment(aptID, patientID, staffID, aptDate, aptTime)
procedures(procNum, pName, price)
aptDetail(aptID, procNo)
So say if I wanted to list the names of patients with appointments with a specific staff member, i.e John Smith, how would I do that explicitly?
I've managed implicitly, but I know this is kind of frowned upon, but I can't reach it without using WHERE statements.
Any help would be appreciated, any time I try and use INNER JOIN I seem to hit a wall if it's not a simple join.
Is this the type of query you're looking for?
select distinct pFname, pLname
from patient p
join appointment a on p.pID = a.patientID
join staff s on a.staffID = s.ID
where s.fname = 'John' and s.lname = 'Smith'
You can use inner join
select
a.pID
, a.pFname
, a.pLname
, a.bdate
, a.address
, a.phone
, b.aptDate
, b.aptTime
, c.fname
, c.lname
, c.role
from patient a
INNER JOIN appointment b on b.patientID = a.pID
INNER JOIN staff c on b.staffID = c.ID on concat(fname, ' ', lname ) ='John Smith'
Something like the following should work fine:
SELECT p.*
FROM appointment AS a
INNER JOIN staff AS s ON a.staffID = s.pID
INNER JOIN patient AS p ON a.patientID = p.pID
WHERE s.ID = <yourstaffid>;
select staff.fname, staff.role,
patient.pfname, plname, appoitment.aotdate
from staff, patient, appointment
where patient.pid=appointment.patientId
and staff.id=appointment.staffid
I want to join the same table to get some information.
I have a Person Table
PersonId, FirstName, LastName, Address
Also Patient Table
PatientId, PersonId, ResponsiblePersonId
Below is the query i tried to get Patient's FirstName, Last Name also the Responsible Person FirstName, Last Name. For this I JOINED Person table once again to get Responsible Persons First, Last names.
But I got many duplicate records.
SELECT PAT.PatientId
,PER.PersonNumber
,PER.FirstName
,PER.LastName
,RES_PER.FirstName AS ResFirstName
,RES_PER.LastName AS ResLastName
,PER.Address
FROM dbo.Patient AS PAT
INNER JOIN dbo.Person AS PER
ON PAT.PersonId = PER.PersonId
INNER JOIN dbo.Person AS RES_PER
ON PAT.ResponsiblePersonId = PER.PersonId
How can i get Patient FirstName, LastName & Responsible Person's First Name, Last Name for the patient record?
Basically, you need to join table Person twice on table Patient in order to get the two dependent columns on it.
SELECT b.FirstName Patient_FirstName,
b.LastName Patient_LastName,
b.Address Patient_Address,
c.FirstName Responsible_Firstname,
c.LastName Responsible_LastName,
c.Address Responsible_Address
FROM Patient a
INNER JOIN Person b
ON a.PersonID = b.PersonID
INNER JOIN Person c
ON a.ResponsiblePersonId = c.PersonID
To further gain more knowledge about joins, kindly visit the link below:
Visual Representation of SQL Joins
All you need to do is replace PER with RES_PER in the very last bit of your SQL. (i.e. PER.PersonId becomes RES_PER.PersonId).
SELECT PAT.PatientId
,PER.PersonNumber
,PER.FirstName
,PER.LastName
,RES_PER.FirstName AS ResFirstName
,RES_PER.LastName AS ResLastName
,PER.Address
FROM dbo.Patient AS PAT
INNER JOIN dbo.Person AS PER
ON PAT.PersonId = PER.PersonId
INNER JOIN dbo.Person AS RES_PER
ON PAT.ResponsiblePersonId = RES_PER.PersonId
I'm running into some difficulty with a query for my databases class. Given the following schema:
Customers (customerid, first_name, last_name, address, city, state, phone, status)
Branches (branchno, address, city, state, phone, manager_name)
Employees (empno, firstname, lastname, address, city, state, phone, emergency_contact, title, managerno)
Rooms (roomno, branchno, price, bed_size)
Bookings (roomno, branchno, customerid, checkin_date, checkout_date, empno)
I'd like to find the customer(s) that have rented the most expensive room. I gave this query a try...
SELECT customerid FROM bookings NATURAL JOIN rooms
EXCEPT
(SELECT customerid FROM (bookings NATURAL JOIN rooms) AS S, (bookings NATURAL JOIN
rooms) as T WHERE S.price < T.price)
The problem comes from the way I want to rename the tables. I'd like to use the natural join of bookings and rooms as components of the Cartesian product... How can I do this?
Thank you very much.
You could use this:
SELECT
customerid
FROM
Bookings
NATURAL JOIN
Rooms
NATURAL JOIN
( SELECT MAX(price) AS price
FROM Rooms
) AS MostExpensiveRoom
Your query seems valid, except that you need to clarify which customerid you want in the second subquery, the S. or the T. one. The comma , syntax means a CROSS JOIN between S and T so you have two customerids:
(SELECT customerid FROM bookings NATURAL JOIN rooms)
EXCEPT
(SELECT S.customerid
FROM
(bookings NATURAL JOIN rooms) AS S
CROSS JOIN
(bookings NATURAL JOIN rooms) AS T
WHERE S.price < T.price
)
SELECT * FROM customers as c
INNER JOIN bookings as b ON b.customerid = c.customerid
INNER JOIN rooms as r ON r.roomno = b.roomno
ORDER BY r.price DESC
LIMIT 1;
if you want only the names, or specified fields, you can use GROUP BY.
This query do the same (if the previous is good syntactically):
SELECT * FROM customers,bookings,rooms
WHERE bookings.customerid = customers.customerid
AND rooms.roomno = bookings.roomno
ORDER BY rooms.price DESC
LIMIT 1
so if you want id-s and names ordered by rent price desc:
SELECT customers.customerid, customers.fistname, customers.lastname FROM
customers,bookings,rooms
WHERE bookings.customerid = customers.customerid
AND rooms.roomno = bookings.roomno
ORDER BY rooms.price DESC
GROUP BY customers.customerid, customers.fistname, customers.lastname
LIMIT 10