SQL query self join - sql

I am working on a query for a report in Oracle 10g.
I need to generate a short list of each course along with the number of times they were offered in the past year (including ones that weren't actually offered).
I created one query
SELECT coursenumber, count(datestart) AS Offered
FROM class
WHERE datestart BETWEEN (sysdate-365) AND sysdate
GROUP BY coursenumber;
Which produces
COURSENUMBER OFFERED
---- ----------
ST03 2
PD01 1
AY03 2
TB01 4
This query is all correct. However ideally I want it to list those along with COURSENUMBER HY and CS in the left column as well with 0 or null as the OFFERED value. I have a feeling this involves a join of sorts, but so far what I have tried doesn't produce the classes with nothing offered.
The table normally looks like
REFERENCE_NO DATESTART TIME TIME EID ROOMID COURSENUMBER
------------ --------- ---- ---- ---------- ---------- ----
256 03-MAR-11 0930 1100 2 2 PD01
257 03-MAY-11 0930 1100 12 7 PD01
258 18-MAY-11 1230 0100 12 7 PD01
259 24-OCT-11 1930 2015 6 2 CS01
260 17-JUN-11 1130 1300 6 4 CS01
261 25-MAY-11 1900 2000 13 6 HY01
262 25-MAY-11 1900 2000 13 6 HY01
263 04-APR-11 0930 1100 13 5 ST03
264 13-SEP-11 1930 2100 6 4 ST03
265 05-NOV-11 1930 2100 6 5 ST03
266 04-FEB-11 1430 1600 6 5 ST03
267 02-JAN-11 0630 0700 13 1 TB01
268 01-FEB-11 0630 0700 13 1 TB01
269 01-MAR-11 0630 0700 13 1 TB01
270 01-APR-11 0630 0700 13 1 TB01
271 01-MAY-11 0630 0700 13 1 TB01
272 14-MAR-11 0830 0915 4 3 AY03
273 19-APR-11 0930 1015 4 3 AY03
274 17-JUN-11 0830 0915 14 3 AY03
275 14-AUG-09 0930 1015 14 3 AY03
276 03-MAY-09 0830 0915 14 3 AY03


SELECT
coursenumber,
COUNT(CASE WHEN datestart BETWEEN (sysdate-365) AND sysdate THEN 1 END) AS Offered
FROM class
GROUP BY coursenumber;
So, as you can see, this particular problem doesn't need a join.


I think something like this should work for you, by just doing it as a subquery.
SELECT distinct c.coursenumber,
(SELECT COUNT(*)
FROM class
WHERE class.coursenumber = c.coursenumber
AND datestart BETWEEN (sysdate-365) AND sysdate
) AS Offered
FROM class c


I like jschoen's answer better for this particular case (when you want one and only one row and column out of the subquery for each row of the main query), but just to demonstrate another way to do it:
select t1.coursenumber, nvl(t2.cnt,0)
from class t1 left outer join (
select coursenumber, count(*) cnt
from class
where datestart between (sysdate-365) AND sysdate
group by coursenumber
) t2 on t1.coursenumber = t2.coursenumber

Related

Access SQL Query to Count Unique Occurrences of One Field Matching Multiple Parameters/Rows, Some Identical

Struggling with ms-access's flavor of SQL queries still, though I've made some progress (thanks to y'all). I have an event log table like this:
Logs Table
logID (auto#)
modID (str)
relID (str)
DateTime (date)
TxType (short)
1
1234
22.3
10/1/22 0800
6
2
1234
22.3
10/1/22 0900
7
3
1234
22.3
10/1/22 1000
13
4
1234
22.3
10/1/22 1100
15
5
4321
22.3
10/1/22 0830
1
6
4321
22.3
10/1/22 0930
13
7
4321
22.3
10/1/22 1030
15
8
4321
22.3
10/1/22 1130
13
9
1234
23.1
11/1/22 0800
1
10
1234
23.1
11/1/22 0900
15
11
1234
23.1
11/1/22 1000
13
12
1234
23.1
11/1/22 1100
15
13
4321
23.1
11/1/22 0830
13
14
4321
23.1
11/1/22 0930
7
15
4321
23.1
11/1/22 1030
13
16
4321
23.1
11/1/22 1130
15
What I need to do is:
filter the table by relID, then
count the number of modID's that have a 15 txType as the last/most recent chronological event in their rows.
So ideally I'd filter e.g. by relID=23.1 and get these results (but not logID # 10 for example) and then count them:
logID (auto#)
modID (str)
relID (str)
DateTime (date)
TxType (short)
12
1234
23.1
11/1/22 1100
15
16
4321
23.1
11/1/22 1130
15
As part of another function I have been able to count any modID's having a single txType successfully using
SELECT COUNT(*)
FROM (
SELECT DISTINCT Logs.modID, Logs.relID
FROM Logs
WHERE ((Logs.relID='23.1') AND ((Logs.TxType=13)))
);
Another stackoverflow user (exception - thanks!) showed me how to get the last event type for a given modID, relID combination using
SELECT TOP 1 TxType
FROM Logs
WHERE (((Logs.modID=[EnterModID])) AND ((Logs.relID=[EnterRelID])))
ORDER BY DateTime DESC;
But I'm having trouble combining these two. I know I can combine COUNT and GROUP BY but Access treats GROUP BY very particularly, and I'm not sure how to use SELECT TOP to get the latest events for each modID rather than just the latest events in the table, period.

This should give you the logID from the row with the latest DateTime for each combination of modIDand your target relID:
PARAMETERS which_relID Text(255);
SELECT DISTINCT
(
SELECT TOP 1 logID
FROM Logs
WHERE modID=l.modID AND relID=l.relID
ORDER BY [DateTime] DESC
) AS latest_modID
FROM Logs AS l
WHERE l.relID=[which_relID]
Use it as a subquery which you INNER JOIN to your Logs table. Note the subquery evaluates rows regardless of TxType. So have the parent query select only rows whose TxType = 15
PARAMETERS which_relID Text(255);
SELECT l2.*
FROM
Logs AS l2
INNER JOIN
(
SELECT DISTINCT
(
SELECT TOP 1 logID
FROM Logs
WHERE modID=l.modID AND relID=l.relID
ORDER BY [DateTime] DESC
) AS latest_modID
FROM Logs AS l
WHERE l.relID=[which_relID]
) AS sub
ON l2.logID=sub.latest_modID
WHERE l2.TxType=15;
Note I moved the PARAMETERS clause into the parent query. But you can eliminate it altogether if you believe it's causing trouble.
DateTime is a reserved word. I enclosed it in square brackets to ensure Access understands we mean the name of an object.
Using your sample data, I get these 2 rows when I supply 23.1 for the query parameter:
logID
modID
relID
DateTime
TxType
12
1234
23.1
11/1/2022 11:00:00 AM
15
16
4321
23.1
11/1/2022 11:30:00 AM
15
I get a single row with 22.3 for the parameter:
logID
modID
relID
DateTime
TxType
4
1234
22.3
10/1/2022 11:00:00 AM
15

What is the best why to aggregate data for last 7,30,60.. days in SQL

Hi I have a table with date and the number of views that we had in our channel at the same day
date views
03/06/2020 5
08/06/2020 49
09/06/2020 50
10/06/2020 1
13/06/2020 1
16/06/2020 1
17/06/2020 102
23/06/2020 97
29/06/2020 98
07/07/2020 2
08/07/2020 198
12/07/2020 1
14/07/2020 168
23/07/2020 292
No we want to see in each calendar date the sum of the past 7 and 30 days
so the result will be
date sum_of_7d sum_of_30d
01/06/2020 0 0
02/06/2020 0 0
03/06/2020 5 5
04/06/2020 5 5
05/06/2020 5 5
06/06/2020 5 5
07/06/2020 5 5
08/06/2020 54 54
09/06/2020 104 104
10/06/2020 100 105
11/06/2020 100 105
12/06/2020 100 105
13/06/2020 101 106
14/06/2020 101 106
15/06/2020 52 106
16/06/2020 53 107
17/06/2020 105 209
18/06/2020 105 209
so I was wondering what is the best SQL that I can write in order to get it
I'm working on redshift and the actual table (not this example) include over 40B rows
I used to do something like this:
select dates_helper.date
, tbl1.cnt
, sum(tbl1.cnt) over (order by date rows between 7 preceding and current row ) as sum_7d
, sum(tbl1.cnt) over (order by date rows between 30 preceding and current row ) as sum_7d
from bi_db.dates_helper
left join tbl1
on tbl1.invite_date = dates_helper.date

matching customer id value in postgresql

new to learning sql/postgresql and have been hunting all over looking for help with a query to find only the matching id values in a table so i can pull data from another table for a learning project. I have been trying to use the count command, which doesn't seem right, and struggling with group by.
here is my table
id acct_num sales_tot cust_id date_of_purchase
1 9001 1106.10 116 12-Jan-00
2 9002 645.22 125 13-Jan-00
3 9003 1096.18 137 14-Jan-00
4 9004 1482.16 118 15-Jan-00
5 9005 1132.88 141 16-Jan-00
6 9006 482.16 137 17-Jan-00
7 9007 1748.65 147 18-Jan-00
8 9008 3206.29 122 19-Jan-00
9 9009 1184.16 115 20-Jan-00
10 9010 2198.25 133 21-Jan-00
11 9011 769.22 141 22-Jan-00
12 9012 2639.17 117 23-Jan-00
13 9013 546.12 122 24-Jan-00
14 9014 3149.18 116 25-Jan-00
trying to write a simple query to only find matching customer id's, and export them to the query window.

how to update duplicate rows in a column to a new values

I will explain my problem briefly
have duplicate rino like below (actually this rino is the serial number in front end)
chqid rino branchid
----- ---- --------
876 6 2
14 6 2
18 10 2
828 10 2
829 11 2
19 11 2
830 12 2
20 12 2
78 40 2
1092 40 2
1094 41 2
79 41 2
413 43 2
1103 43 2
82 44 2
1104 44 2
1105 45 2
83 45 2
91 46 2
1106 46 2
here in my case I don't want to delete these duplicate rino instead of that I planned to update the rino having max date(column not specified in the above sample actually a date column is there) to the next rino number
what exactly I meant is :
if I sort out the above result according to the max(date) I will get
chqid rino branchid
----- ---- --------
876 6 2
828 10 2
19 11 2
830 12 2
1092 40 2
79 41 2
413 43 2
82 44 2
83 45 2
1106 46 2
(NOTE : total number of duplicate rows are 10 in branchid=2)
the last entered rino in the table for branchid=2 is 245
So I just want to update the 10 rows(Of column rino) with numbers starting from 246 to 255( just added 245+10 like this select lastno+ generate_series(1,10) nos from tab where cola=4 and branchid = 2 and vrid=20;)
Expected Output:
chqid rino branchid
----- ---- --------
876 246 2
828 247 2
19 248 2
830 249 2
1092 250 2
79 251 2
413 252 2
82 253 2
83 254 2
1106 255 2
using postgresql

Finally I found a solution, am using dynamic-sql to solve my issue
do
$$
declare
arow record;
begin
for arow in
select chqid,rino,branchid from (
select chqid,rino::int ,vrid,branchid ,row_number()over (partition by rino::int ) rn
from tab
where vrid =20
and branchid = 2)t
where rn >1
loop
execute format('
update tab
set rino=(select max(rino::int)+1 from gtab19 where acyrid=4 and branchid = 2 and vrid=20)
where chqid=%s
',arow.chqid);
end loop;
end;
$$;

Update or Select into ORACLE

I am using the following statement;
SELECT RESV_ID, BOOKING_CUS_ID, ACC_ID,
(SELECT F.FLI_PRICE FROM FLIGHT F WHERE F.FLI_ID = R.IN_FLIGHT_ID) AS DEPART_FLIGHT_PRICE,
(SELECT F1.FLI_PRICE FROM FLIGHT F1 WHERE F1.FLI_ID = R.OUT_FLIGHT_ID) AS RETURN_FLIGHT_PRICE,
(SELECT AC.ACC_PRICEPN FROM ACCOMMODATION AC WHERE AC.ACC_ID = R.ACC_ID) AS ACCOMMODATION_PRICE
FROM HOLIDAY_RESERVATION R;
to yield the following results;
RESV_ID BOOKING_CUS_ID ACC_ID DEPART_FLIGHT_PRICE RETURN_FLIGHT_PRICE ACCOMMODATION_PRICE
---------- -------------- ---------- ------------------- ------------------- -------------------
1 1 2 520 450 350
2 3 4 250 150 150
3 5 6 290 300 450
4 7 7 399 450 650
5 9 365 345
6 11 558 460
7 13 250 250
8 15 550 550
9 17 25 250
10 19 19 450
10 rows selected.
Question:
How do I sum up the price fields, SOME PRICES ARE NOT AVAILABLE because a reservation was either made for accommodation only or flight only, hence both values will not be present always and this is where the issue lies
DEPART_FLIGHT_PRICE RETURN_FLIGHT_PRICE ACCOMMODATION_PRICE
Furthermore:
I wish to insert or update the SUM of those three values into a SUBTOTAL in the reservation table, perhaps by using select into or update, I have spent a whole day trying to do this but my skills are limited. any help will be greatly appreciated.
Flight table
FLI_ID FLI_CO FLI_AIRCRA DEPT_AIRPORT ARRV_AIRPORT DEPT_TIME ARRV_TIME FLI_PRICE
1 BD425 Boeing 707 1 12 18-MAR-12 02.24.00 AM 18-MAR-12 06.24.00 AM 520
2 LX345 Beriev 30 6 7 20-MAR-12 03.30.00 PM 20-MAR-12 04.20.00 PM 250
3 NZ4445 Boeing 720 9 14 25-MAR-12 09.00.00 AM 25-MAR-12 05.00.00 PM 290
4 TP351 Boeing 767 10 15 25-MAR-12 11.25.00 AM 25-MAR-12 03.35.00 PM 399
5 BA472 Boeing 720 5 14 26-MAR-12 01.05.00 PM 26-MAR-12 04.15.00 PM 365
Accommodation
ACC_ID ACC_TYPE_CODE ACC_DESC ACC_PRICEPN ACC_ROOMS RESORT_ID ACC_ADDR CITY_ID
1 1 Three bedroom bungalow near theme park 500 3 1
2 1 Two bedroom bungalow next to disney house 350 2 1
3 1 One bedroom bungalow with lake view 250 2 2
4 2 One bedroom chalet near the lake 150 1 2
5 2 Four bedroom chalet near the tree house 600 4 3
Reservation
RESV_ID EMP_ID BOOKING_CUS_ID RESV_DATE HOLIDAY_S HOLIDAY_E IN_FLIGHT_ID OUT_FLIGHT_ID IN_FLIGHT_SEATS_NO OUT_FLIGHT_SEATS_NO ACC_ID SUBTOTAL
1 338 1 16-FEB-12 18-MAR-12 20-APR-12 1 11 2 2 2
2 335 3 10-JAN-12 20-MAR-12 22-APR-12 2 12 2 2 4
3 338 5 05-MAR-12 25-MAR-12 26-APR-12 3 13 2 2 6
4 328 7 02-JAN-12 25-MAR-12 25-APR-12 4 14 2 2 7
5 311 9 20-JAN-12 26-MAR-12 21-APR-12 5 15 2 2
6 317 11 07-JAN-12 27-MAR-12 22-APR-12 6 16 2 2
7 344 13 29-FEB-12 15-MAR-12 12-APR-12 7 17 2 2
8 326 15 11-JAN-12 18-MAR-12 12-APR-14 8 18 2 2
9 329 17 16-JAN-12 19-MAR-12 17-APR-12 25
10 323 19 18-FEB-12 20-MAR-12 21-APR-12 19
Okay I managed to yield the results that i wanted
SELECT HR.RESV_ID, F_IN.FLI_ID, F_IN.FLI_PRICE, F_OUT.FLI_ID, F_OUT.FLI_PRICE, AC.ACC_ID, AC.ACC_PRICEPN, NVL(F_IN.FLI_PRICE,0)+NVL(F_OUT.FLI_PRICE,0)+NVL(AC.ACC_PRICEPN,0) AS TOTAL
FROM HOLIDAY_RESERVATION HR
LEFT JOIN FLIGHT F_IN ON HR.IN_FLIGHT_ID = F_IN.FLI_ID
LEFT JOIN FLIGHT F_OUT ON HR.OUT_FLIGHT_ID = F_OUT.FLI_ID
LEFT JOIN ACCOMMODATION AC ON HR.ACC_ID = AC.ACC_ID
ORDER BY HR.RESV_ID;
YIELDS
RESV_ID FLI_ID FLI_PRICE FLI_ID FLI_PRICE ACC_ID ACC_PRICEPN TOTAL
---------- ---------- ---------- ---------- ---------- ---------- ----------- ----------
1 1 500 11 555 2 350 1405
2 2 150 12 253 4 150 553
3 3 300 13 345 6 450 1095
4 4 450 14 343 7 650 1443
5 5 345 15 242 587
6 6 460 16 460 920
7 7 250 17 250 500
8 8 550 18 550 1100
9 25 250 250
10 19 450 450
And the following statement is to update the reservation table.
Thanks to Leigh Riffel from DBA stackxchange for the following code
UPDATE HOLIDAY_RESERVATION R SET SUBTOTAL =
NVL((SELECT F.FLI_PRICE FROM FLIGHT F WHERE F.FLI_ID = R.IN_FLIGHT_ID), 0) +
NVL((SELECT F.FLI_PRICE FROM FLIGHT F WHERE F.FLI_ID = R.OUT_FLIGHT_ID), 0) +
NVL((SELECT AC.ACC_PRICEPN FROM ACCOMMODATION AC WHERE AC.ACC_ID = R.ACC_ID), 0);
Now the subtotal is populated with the values obtained from the sum performed above >>
RESV_ID EMP_ID BOOKING_CUS_ID RESV_DATE HOLIDAY_S HOLIDAY_E IN_FLIGHT_ID OUT_FLIGHT_ID IN_FLIGHT_SEATS_NO OUT_FLIGHT_SEATS_NO ACC_ID SUBTOTAL
---------- ---------- -------------- --------- --------- --------- ------------ ------------- ------------------ ------------------- ---------- ----------
1 338 1 16-FEB-12 18-MAR-12 20-APR-12 1 11 2 2 2 1405
2 335 3 10-JAN-12 20-MAR-12 22-APR-12 2 12 2 2 4 553
3 338 5 05-MAR-12 25-MAR-12 26-APR-12 3 13 2 2 6 1095
4 328 7 02-JAN-12 25-MAR-12 25-APR-12 4 14 2 2 7 1443
5 311 9 20-JAN-12 26-MAR-12 21-APR-12 5 15 2 2 587
6 317 11 07-JAN-12 27-MAR-12 22-APR-12 6 16 2 2 920
7 344 13 29-FEB-12 15-MAR-12 12-APR-12 7 17 2 2 500
8 326 15 11-JAN-12 18-MAR-12 12-APR-14 8 18 2 2 1100
9 329 17 16-JAN-12 19-MAR-12 17-APR-12 25 250
10 323 19 18-FEB-12 20-MAR-12 21-APR-12 19 450
Subsequently the code was added to a trigger (which was the original intention)
CREATE OR REPLACE TRIGGER HR_SUBTOTAL
BEFORE INSERT OR UPDATE ON HOLIDAY_RESERVATION
FOR EACH ROW
BEGIN
SELECT
NVL((SELECT F.Fli_Price FROM Flight F WHERE F.Fli_ID = :new.In_Flight_ID), 0) +
NVL((SELECT F.Fli_Price FROM Flight F WHERE F.Fli_ID = :new.Out_Flight_ID), 0) +
NVL((SELECT AC.Acc_PricePn FROM Accomodation AC WHERE AC.Acc_ID = :new.Acc_ID), 0)
INTO :new.Subtotal
FROM dual;
END;
/

For the SUM, assuming you want to treat NULL values as 0, you'd just need to do an NVL on the numbers
NVL( DEPART_FLIGHT_PRICE, 0 ) +
NVL( RETURN_FLIGHT_PRICE, 0 ) +
NVL( ACCOMMODATION_PRICE, 0 )
As for the UPDATE, it sounds like you just need a correlated UPDATE statement.
UPDATE reservation r
SET subtotal = (SELECT (SELECT NVL( DEPART_FLIGHT_PRICE, 0 ) +
NVL( RETURN_FLIGHT_PRICE, 0 ) +
NVL( ACCOMMODATION_PRICE, 0 )
FROM (SELECT RESV_ID,
BOOKING_CUS_ID,
ACC_ID,
(SELECT F.FLI_PRICE
FROM FLIGHT F
WHERE F.FLI_ID = R.IN_FLIGHT_ID) AS DEPART_FLIGHT_PRICE,
(SELECT F1.FLI_PRICE
FROM FLIGHT F1
WHERE F1.FLI_ID = R.OUT_FLIGHT_ID) AS RETURN_FLIGHT_PRICE,
(SELECT AC.ACC_PRICEPN
FROM ACCOMMODATION AC
WHERE AC.ACC_ID = R.ACC_ID) AS ACCOMMODATION_PRICE
FROM dual));

You are asking:
How do I sum up the price fields, as you can see some of them can have nulls.
DEPART_FLIGHT_PRICE RETURN_FLIGHT_PRICE ACCOMMODATION_PRICE
Just enclose them in NVL function as follows:
NVL(DEPART_FLIGHT_PRICE, 0)
and then sum them up.
For the second part, what you need is a MERGE statement. A good example is at http://www.oracle-developer.net/display.php?id=203