I have been working on the mimic II database and I don't understand how to use joins between 3 tables.
Currently I have:
SELECT p.hospital_expire_flg,
COUNT (*)
FROM poe_med m, poe_order o, d_patients p
WHERE m.poe_id=o.poe_id
AND o.subject_id=p.subject_id
AND drug_name_generic = 'Metoprolol'
GROUP BY p.hospital_expire_flg
I'm guessing I have to use JOIN AS for the 3 tables. But not sure how to.
You can do:
SELECT p.hospital_expire_flg
FROM poe_med `m`
INNER JOIN poe_order `o`
ON m.poe_id = o.poe_id
INNER JOIN d_patients p
ON o.subject_id = p.subject_id
WHERE drug_name_generic = 'Metroprolol';
Related
I have this code:
SELECT A.UNITCODE, B.FORMATIONCODE, C.UPPERFORMATIONCODE, D.UPPERFORMATIONCODE
FROM UNIT AS A.UNITCODE
INNER JOIN FORMATION AS B.FORMATIONCODE
INNER JOIN UPPERFORMATION_UNIT AS C.UPPERFORMATION
INNER JOIN UPPERFORMATION AS D.UPPERFORMATIONCODE
WHERE UNITCODE='7000007'
Can you guys help me how to join 4 tables with specified column?
Assuiming the all 3 related tables have the same UNIT_ID for join with table UNIT
SELECT
A.UNITCODE
, B.FORMATIONCODE
, C.UPPERFORMATIONCODE
, D.UPPERFORMATIONCODE
FROM UNIT AS A
INNER JOIN FORMATION AS B ON B.FORMATIONCODE = A.UNIT_ID
INNER JOIN UPPERFORMATION_UNIT AS C. C.UPPERFORMATION = A.UNIT_ID
INNER JOIN UPPERFORMATION AS D D.UPPERFORMATIONCODE = A.UNIT_ID
WHERE UNITCODE='7000007'
It seems you are confusing table aliases and linking columns.
This is how to give a table an alias name in the query in order to enhance readability:
INNER JOIN formation AS f
where the AS is optional. Most often it is ommited.
This is how to join:
FROM unit AS u
INNER JOIN upperformation_unit AS ufu ON ufu.unitcode = u.unitcode
Well, I don't know the columns linking the tables of course, let alone their names. But I suppose the query would have to look like this more or less:
SELECT
u.unitcode,
f.formationcode,
uf.upperformationcode,
ufu.upperformationcode
FROM unit u
JOIN upperformation_unit ufu ON ufu.unitcode = u.unitcode
JOIN upperformation uf ON uf.upperformationcode = ufu.upperformationcode
JOIN formation f ON f.formationcode uf.formationcode
WHERE u.unitcode = 7000007;
I am having 3 tables named customers,cars,carrent. All i want is to multiply rentorder.days with cardetail.rentday and show the value in rentorder.totalrent. I am unable to achieve this. How can i do this.
Any suggestions please.
SQL
SELECT customers.*,
cardetail.carname,
cardetail.model,
cardetail.company,
cardetail.color,
cardetail.rentday,
rentorder.days,
rentorder.totalrent
FROM rentorder
INNER JOIN customers
ON customers.custid = rentorder.custid
INNER JOIN cardetail
ON cardetail.id = rentorder.carid
Just multiply rentday with days to get the computed value totalrent in Select list.
Try this
SELECT customers.*, -- Not sure this is allowed in [Mysql]
cardetail.carname,
cardetail.model,
cardetail.company,
cardetail.color,
cardetail.rentday,
rentorder.days,
cardetail.rentday * rentorder.days AS totalrent
FROM rentorder
INNER JOIN customers
ON customers.custid = rentorder.custid
INNER JOIN cardetail
ON cardetail.id = rentorder.carid
To save the data you need to use update from Inner Join syntax
update rentorder
INNER JOIN customers
ON customers.custid = rentorder.custid
INNER JOIN cardetail
ON cardetail.id = rentorder.carid
SET
rentorder.totalrent = cardetail.rentday * rentorder.days
A bit of a newbie question, probably an INNER JOIN with an "AS" statement, but I can't figure it out...
This is for a MYSQL based competition app. I want to select the "img_title" for both img_id1 and img_id2. I can't figure out how to do it and still see which title is assigned to the associated _id1 or _id2.
My tables:
competitions
comp_id
img_id1
img_id2
on_deck
img_id
img_title
Desired results:
comp_id | img_id1 | img_title1 |img_id2 | img_title2
You need a join for each image:
SELECT comp.comp_id, img1.img_id, img1.img_title, img2.img_id, img2.img_title
FROM competitions comp
INNER JOIN on_deck img1 ON img1.img_id = comp.img_id1
INNER JOIN on_deck img2 ON img2.img_id = comp.img_id2
LEFT JOIN if img_id1 or img_id2 can be NULL.
select comp_id, img_id1, b.img_title as img_title1,
img_id2, b2.img_title as img_title2
from competitions a
left outer join on_deck b on b.img_id = a.img_id1
left outer join on_deck b2 on b2.img_id = a.img_id2
switch let outer join to inner join if you want to exclude rows in competitions that do not have two matching img_ids
This query should give you the results you want. This also assumes that comp.img_id1 and comp.img_id2 are never NULL.
SELECT comp.comp_id
, comp.img_id1
, deck1.img_title AS img_title1
, comp.img_id2
, deck2.img_title AS img_title2
FROM competitions AS comp
JOIN on_deck deck1 ON comp.img_id1 = deck1.img_id
JOIN on_deck deck2 ON comp.img_id2 = deck2.img_id
If you have plan on having a NULL or empty string comp.img_id1 and/or comp.img_id2 fields, you'll need to do some left joins.
I'm trying to make a count within several table with JOIN, but when I made several JOINs the COUNTs got wrongly counted.
Basically I've got 4 tables, named:
predective_search
predective_to_product
predective_to_category
predective_to_manufacturer
I want to count the total number of products, categories and manufacturer which has same id in table predective_search.
Here's my code:
SELECT * ,
COUNT(pp.predictive_id) AS total_products,
COUNT(pc.predictive_id) AS total_categories,
COUNT(pm.predictive_id) AS total_manufacturers
FROM predictive_search ps
LEFT JOIN predictive_to_product pp ON (ps.predictive_id = pp.predictive_id)
LEFT JOIN predictive_to_category pu ON (ps.predictive_id = pc.predictive_id)
LEFT JOIN oc_predictive_to_manufacturer pm ON (ps.predictive_id = pm.predictive_id)
GROUP BY ps.predictive_id
Also the GROUP BY is needed I think. I'm stuck at this as I'm not getting any way to do this
SELECT
ps.*,
agg_pp.total_products,
agg_pc.total_categories,
agg_pm.total_manufacturers
FROM predictive_search ps
LEFT JOIN (
SELECT pp.predictive_id, COUNT(*) AS total_products
FROM predictive_to_product pp
GROUP BY pp.predictive_id
) agg_pp ON ps.predictive_id = agg_pp.predictive_id
LEFT JOIN (
SELECT pc.predictive_id, COUNT(*) AS total_categories
FROM predictive_to_category pc
GROUP BY pc.predictive_id
) agg_pc ON ps.predictive_id = agg_pc.predictive_id
LEFT JOIN (
SELECT pm.predictive_id, COUNT(*) AS total_manufacturers
FROM predictive_to_category pm
GROUP BY pm.predictive_id
) agg_pm ON ps.predictive_id = agg_pm.predictive_id
Here is my view creation.. Which is not returning any rows..
CREATE VIEW TOP AS
(
SELECT
a.USER_ID, a.USER_NAME, a.PASSWORD, a.FIRST_NAME, a.LAST_NAME, a.CONTACT_NUMBER, a.EMERGENCY_NUMBER, a.CITIZEN_SHIP, a.VISA_TYPE,
b.PLACE_CODE, b.PLACE_NAME, b.AIR_AVAILIBILITY, b.TRAIN_AVAILIBILITY, b.ROAD_AVAILIBILITY,
c.CLIENT_ID, c.CLIENT_NAME, c.CLIENT_ADDRESS, c.CLIENT_LOCATION,
d.PROJECT_CODE, d.PROJECT_NAME,
e.REQUEST_ID, e.REQUEST_STATUS, e.REQUEST_FOR, e.REQUEST_MODE, e.REQUEST_TYPE, e.TRAVEL_FROM, e.TRAVEL_TO, e.TRAVEL_DATE, e.TRAVEL_TICKET_BY, e.ASSIGNMENT_PLACE,
e.ASSIGNMENT_COUNTRY, e.TRAVEL_PURPOSE, e.ASSIGNMENT_DURATION, e.ASSIGNMENT_START_DATE, e.ASSIGNMENT_ACCOMODATION_BY, e.ACCOMODATION_BILLABLE, e.TRAVEL_BILLABLE, e.ASSIGNMENT_BILLABLE, e.NSHORE_PROJECT_BILLABLE
FROM USERS a, PLACES b, CLIENTS c, PROJECTS d, REQUESTS e
WHERE
a.USER_ID = e.USER_ID
AND b.PLACE_CODE = e.TRAVEL_FROM
AND b.PLACE_CODE = e.TRAVEL_TO
AND c.CLIENT_ID = d.CLIENT_ID
AND d.PROJECT_CODE = e.PROJECT_CODE
);
I think the problem is in these two lines..
AND b.PLACE_CODE = e.TRAVEL_FROM
AND b.PLACE_CODE = e.TRAVEL_TO
where I'm trying to reference to the same table more than once. Sorry if I'm asking really a very basic question. Im completely new to databases.
Looks like you are trying to get separate details for the place TRAVEL_FROM and the place TRAVEL_TO. To do that, you need to join twice against the same table with different aliases. I'm going to replace your implicit (comma-separated FROM) joins with explicit INNER JOINs which are preferred:
CREATE VIEW TOP AS
(
SELECT
a.USER_ID, a.USER_NAME, a.PASSWORD, a.FIRST_NAME, a.LAST_NAME, a.CONTACT_NUMBER, a.EMERGENCY_NUMBER, a.CITIZEN_SHIP, a.VISA_TYPE,
/* one set of columns for TRAVEL_FROM, each with its own alias */
b_from.PLACE_CODE AS PLACE_CODE_from, b_from.PLACE_NAME AS PLACE_NAME_from, b_from.AIR_AVAILIBILITY AS AIR_AVAILABILITY_from, b_from.TRAIN_AVAILIBILITY AS TRAIN_AVAILABILITY_from, b_from.ROAD_AVAILIBILITY AS ROAD_AVAILABILITY_from,
/* and one set for TRAVEL_TO, each with its own alias*/
b_to.PLACE_CODE AS PLACE_CODE_to, b_to.PLACE_NAME AS PLACE_NAME_to, b_to.AIR_AVAILIBILITY AS AIR_AVAILABILITY_to, b_to.TRAIN_AVAILIBILITY AS TRAIN_AVAILABILITY_to, b_to.ROAD_AVAILIBILITY AS ROAD_AVAILABILITY_to,
c.CLIENT_ID, c.CLIENT_NAME, c.CLIENT_ADDRESS, c.CLIENT_LOCATION,
d.PROJECT_CODE, d.PROJECT_NAME,
e.REQUEST_ID, e.REQUEST_STATUS, e.REQUEST_FOR, e.REQUEST_MODE, e.REQUEST_TYPE, e.TRAVEL_FROM, e.TRAVEL_TO, e.TRAVEL_DATE, e.TRAVEL_TICKET_BY, e.ASSIGNMENT_PLACE,
e.ASSIGNMENT_COUNTRY, e.TRAVEL_PURPOSE, e.ASSIGNMENT_DURATION, e.ASSIGNMENT_START_DATE, e.ASSIGNMENT_ACCOMODATION_BY, e.ACCOMODATION_BILLABLE, e.TRAVEL_BILLABLE, e.ASSIGNMENT_BILLABLE, e.NSHORE_PROJECT_BILLABLE
FROM
/* implicit joins replaced with preferred explicit joins */
USERS a
INNER JOIN REQUESTS e ON a.USER_ID = e.USER_ID
/* Join frist against PLACES for TRAVEL_FROM */
INNER JOIN PLACES b_from ON b_from.PLACE_CODE = e.TRAVEL_FROM
/* And again against PLACES for TRAVEL_TO */
INNER JOIN PLACES b_to ON b_to.PLACE_CODE = e.TRAVEL_TO
INNER JOIN PROJECTS d ON d.PROJECT_CODE = e.PROJECT_CODE
INNER JOIN CLIENTS c ON c.CLIENT_ID = d.CLIENT_ID
);