My Oracle table has the columns: message_id, status, status_date
I would like to return message_id where when grouping by message_id the record with the mininum value for status_date has a value of 'PC' in the status column.
In other words do not return the record if the record that is returned with the minimum value of status_date when grouped by mess_id does not have a value of 'PC' in the status column.
Thanks,
Brian
I'm guessing this is what the source data may look like:
message_id status status_date
---------- ------ -----------
1 PC 01-JAN-12
1 QC 02-JAN-12
1 RC 03-JAN-12
2 AA 04-JAN-12
2 PC 05-JAN-12
2 CC 06-JAN-12
3 PC 07-JAN-12
3 PC 08-JAN-12
3 PC 09-JAN-12
And that the expected output would be something like this:
message_id
----------
1
3
The reason that these two records are returned are because for all the records where message_id=1, the one with the minimum status_date has a value of 01-JAN-12. The record with message_id=1 and status_date of 01-JAN-12 has a status of 'PC', and similarly with message_id=3. Since the minimum status_date of the records with message_id=2 is 04-JAN-12, and it's status is NOT 'PC'.
We can build this query using inline views, but there's probably an easier way using analytic functions.
SELECT A.MESSAGE_ID
FROM MY_TABLE A,
( SELECT B.MESSAGE_ID, MIN(B.STATUS_DATE) MIN_DATE
FROM MY_TABLE B
GROUP BY B.MESSAGE_ID ) C
WHERE A.STATUS = 'PC'
AND A.STATUS_DATE = C.STATUS_DATE
AND A.MESSAGE_ID = C.MESSAGE_ID;
Related
I am looking for a possibly better approach to this.
I have created a temp table in Oracle 11.2 that I'm using to pre calculate values that I will need in other selects instead of always generating them again with each select.
create global temporary table temp_foo (
DT timestamp(6), --only the date part will be used in this example but for later things I will need the time
Something varchar2(100),
Customer varchar2(100),
MinDate timestamp(6),
MaxDate timestamp(6),
Filecount int,
Errorcount int,
AvgFilecount int,
constraint PK_foo primary key (DT, Customer)
) on commit preserve rows;
I then first insert some fixed values for everything except AvgFilecount. AvgFilecount should contain the average for the Filecount for the 3 previous records (going by the date in DT). It doesn’t matter that the result will be converted to an int, I don’t need the decimal places
DT | Customer | Filecount | AvgFilecount
2019-04-30 | x | 10 | avg(2+3+9)
2019-04-29 | x | 2 | based on values before this
2019-04-28 | x | 3 | based on values before this
2019-04-27 | x | 9 | based on values before this
I thought about using a normal UPDATE statement as this should be faster than looping through the values. I should mention that there are no gaps in the DT field but obviously there is a first one where I won‘t find any previous records. If I would loop through, I could easily calculate AvgFilecount with (the record before previous record/2 + previous record)/3 which I cannot with UPDATE as I cannot guarantee the order of how they are executed. So I‘m fine with just taking the last 3 records (going by DT) and calcuting it from there.
What I thought would be an easy update is giving me headaches. I‘m mostly doing SQL Server where I would just join the 3 other records but it seems is a bit different in Oracle. I have found https://stackoverflow.com/a/2446834/4040068 and wanted to use the second approach in the answer.
update
(select curr.DT, curr.temp_foo, curr.Filecount, curr.AvgFilecount as OLD, (coalesce(Minus1.Filecount, 0) + coalesce(Minus2.Filecount, 0) + coalesce(Minus3.Filecount, 0)) / 3 as NEW
from temp_foo curr
left join temp_foo Minus1 ON Minus1.Customer = curr.Customer and trunc(Minus1.DT) = trunc(curr.DT-1)
left join temp_foo Minus2 ON Minus2.Customer = curr.Customer and trunc(Minus2.DT) = trunc(curr.DT-2)
left join temp_foo Minus3 ON Minus3.Customer = curr.Customer and trunc(Minus3.DT) = curr.DT-3
order by 1, 2
)
set OLD = NEW;
Which gives me an
ORA-01779: cannot modify a column which maps to a non key-preserved
table
01779. 00000 - "cannot modify a column which maps to a non key-preserved table"
*Cause: An attempt was made to insert or update columns of a join view which
map to a non-key-preserved table.
*Action: Modify the underlying base tables directly.
I thought this should work as both join conditions are in the primary key and thus unique. I am currently implementing the first approach in the above mentioned answer but it is getting quite big and it feels like there should be a better solution to this.
Other things I thought about trying:
using a nested subselect (nested because Oracle doesn’t know top(n) and I need to sort the subselect) to select the previous 3 records ordered by DT and then he outer select with rownum <=3 and then I could just use AVG(). However, I was told subselect can be quite slow and joins are better in Oracle performance wise. Dunno if that is really the case, haven‘t done any testing
Edit: My insert right now looks like this. I am already aggregating the Filecount for a day as there can be multiple records per DT per Customer per Something.
insert into temp_foo (DT, Something, Customer, Filecount)
select dates.DT, tbl1.Something, tbl1.Customer, coalesce(sum(tbl3.Filecount),0)
from table(Function_Returning_Daterange(NULL, NULL)) dates
cross join
(SELECT Something,
Code,
Value
FROM Table2 tbl2
WHERE (Something = 'Value')) tbl1
left outer join Table3 tbl3
on tbl3.Customer = tbl1.Customer
and trunc(tbl3.MinDate) = trunc(dates.DT)
group by dates.DT, tbl1.Something, tbl1.Customer;
You could use an analytic average with a window clause:
select dt, customer, filecount,
avg(filecount) over (partition by customer order by dt
rows between 3 preceding and 1 preceding) as avgfilecount
from tmp_foo
order by dt desc;
DT CUSTOMER FILECOUNT AVGFILECOUNT
---------- -------- ---------- ------------
2019-04-30 x 10 4.66666667
2019-04-29 x 2 6
2019-04-28 x 3 9
2019-04-27 x 9
and then do the update part with a merge statement:
merge into tmp_foo t
using (
select dt, customer,
avg(filecount) over (partition by customer order by dt
rows between 3 preceding and 1 preceding) as avgfilecount
from tmp_foo
) s
on (s.dt = t.dt and s.customer = t.customer)
when matched then update set t.avgfilecount = s.avgfilecount;
4 rows merged.
select dt, customer, filecount, avgfilecount
from tmp_foo
order by dt desc;
DT CUSTOMER FILECOUNT AVGFILECOUNT
---------- -------- ---------- ------------
2019-04-30 x 10 4.66666667
2019-04-29 x 2 6
2019-04-28 x 3 9
2019-04-27 x 9
You haven't shown your original insert statement; it might be possible to add the analytic calculation to that, and avoid the separate update step.
Also, if you want the first two date values to be calculated as if the 'missing' extra days before them had zero counts, you could use sum and division instead of avg:
select dt, customer, filecount,
sum(filecount) over (partition by customer order by dt
rows between 3 preceding and 1 preceding)/3 as avgfilecount
from tmp_foo
order by dt desc;
DT CUSTOMER FILECOUNT AVGFILECOUNT
---------- -------- ---------- ------------
2019-04-30 x 10 4.66666667
2019-04-29 x 2 4
2019-04-28 x 3 3
2019-04-27 x 9
It depends what you expect those last calculated values to be.
I have a below table - AccountDetails
Account_No Request_Id Issue_date Amount Details
1 567 20150607 $156 Loan
2 789 20170406 $765 Personal
3 20170216 $897
3 987 20160525 $345 Loan
3 456 20170112 $556 Loan
4 234 20171118 $987 Loan
I have to update the request_id where request id is null or Details is null for the account with below logic.
Need to get the latest request id for the account based on the issue date and have to update the request id (latest request id + 1) WHERE request_id is null or details is null. So the result should be
Account No Request_Id Issue_date Amount Details
1 567 20150607 $156 Loan
2 789 20170406 $765 Personal
3 457 20170216 $897
3 987 20160525 $345 Loan
3 456 20170112 $556 Loan
4 234 20171118 $987 Loan
I tried with the below query
MERGE INTO AccountDetails a
USING ( select Request_Id + 1,ROW_NUMBER() OVER (PARTITION BY B.Account_No
ORDER BY B.Issue_date desc) AS RANK_NO
from AccountDetails ) b
ON ( a.Account_No = b.Account_No AND a.DETAILS IS NULL)
WHEN MATCHED THEN
UPDATE SET a.Request_Id = b.Request_Id
WHERE B.RANK_NO = 1;
Sounds like you need to use the analytic LAG function to determine the previous row's request_id, e.g.:
MERGE INTO account_details tgt
USING (SELECT account_no,
CASE WHEN request_id IS NULL THEN 1 + LAG(request_id) OVER (PARTITION BY account_no ORDER BY issue_date)
ELSE request_id
END request_id,
issue_date,
amount,
DETAILS,
ROWID r_id
FROM accountdetails) src
ON (tgt.rowid = src.r_id)
WHEN MATCHED THEN
UPDATE SET tgt.request_id = src.request_id;
Of course, this design seems a little odd - why is request_id null in the first place? Is it a unique column? If so, what happens if you end up duplicating an existing request_id with your replacement id? Also, what should happen if it's the first row in for an account number that's got a null request_id?
update accountdetails set request_id=(select max(request_id)+1 from accountdetails)
where request_id is null and details is null;
First, I execute the following SQL statements.
drop table names;
drop table ages;
create table names (id number, name varchar2(20));
insert into names values (1, 'Harry');
insert into names values (2, 'Sally');
insert into names values (3, 'Barry');
create table ages (id number, age number);
insert into ages values (1, 25);
insert into ages values (2, 30);
insert into ages values (3, 35);
select * from names;
select * from ages;
As a result, the following tables are created.
ID NAME
---------- ----------
1 Harry
2 Sally
3 Barry
ID AGE
---------- ----------
1 25
2 30
3 35
Now, I want to update increment the age of Sally by 1, i.e. set it to 31. The following query works fine.
update ages set age = age + 1 where id = (select id from names where name = 'Sally');
select * from ages;
The table now looks like this.
ID AGE
---------- ----------
1 25
2 31
3 35
I want to know if there is a way it can be done by joins. For example, I tried the following queries but they fail.
SQL> update ages set age = age + 1 from ages, names where ages.id = names.id and names.name = 'Sally';
update ages set age = age + 1 from ages, names where ages.id = names.id and names.name = 'Sally'
*
ERROR at line 1:
ORA-00933: SQL command not properly ended
SQL> update ages set age = age + 1 from names join ages on ages.id = names.id where names.name = 'Sally';
update ages set age = age + 1 from names join ages on ages.id = names.id where names.name = 'Sally'
*
ERROR at line 1:
ORA-00933: SQL command not properly ended
The syntax of the UPDATE statement is:
http://docs.oracle.com/cd/B19306_01/server.102/b14200/statements_10007.htm
where dml_table_expression_clause is:
Please pay attention on ( subquery ) part of the above syntax.
The subquery is a feature that allows to perform an update of joins.
In the most simplest form it can be:
UPDATE (
subquery-with-a-join
)
SET cola=colb
Before update a join, you must know restrictions listed here:
https://docs.oracle.com/cd/B28359_01/server.111/b28286/statements_8004.htm
The view must not contain any of the following constructs:
A set operator
A DISTINCT operator
An aggregate or analytic function
A GROUP BY, ORDER BY, MODEL, CONNECT BY, or START WITH clause
A collection expression in a SELECT list
A subquery in a SELECT list
A subquery designated WITH READ ONLY
Joins, with some exceptions, as documented in Oracle Database Administrator's Guide
and also common rules related to updatable views - here (section: Updating a Join View):
http://docs.oracle.com/cd/B19306_01/server.102/b14231/views.htm#sthref3055
All updatable columns of a join view must map to columns of a
key-preserved table. See "Key-Preserved Tables" for a discussion of
key-preserved tables. If the view is defined with the WITH CHECK
OPTION clause, then all join columns and all columns of repeated
tables are not updatable.
We can first create a subquery with a join:
SELECT age
FROM ages a
JOIN names m ON a.id = m.id
WHERE m.name = 'Sally'
This query simply returns the following result:
AGE
----------
30
and now we can try to update our query:
UPDATE (
SELECT age
FROM ages a
JOIN names m ON a.id = m.id
WHERE m.name = 'Sally'
)
SET age = age + 1;
but we get an error:
SQL Error: ORA-01779:cannot modify a column which maps to a non key-preserved table
This error means, that one of the above restriction is not meet (key-preserved table).
However if we add primary keys to our tables:
alter table names add primary key( id );
alter table ages add primary key( id );
then now the update works without any error and a final outcome is:
select * from ages;
ID AGE
---------- ----------
1 25
2 31
3 35
I have source table and a target table I want to do merge such that there should always be insert in the target table. For each record updated there should ne a flag updated to 'Y' and when this in something is changed then record flag value should be chnaged to 'N' and a new row of that record is inserted in target such that the information of record that is updated should be reflected. Basically I want to implement SCD type2 . My input data is-
student_id name city state mobile
1 suraj bhopal m.p. 9874561230
2 ravi pune mh 9874563210
3 amit patna bihar 9632587410
4 rao banglore kr 9236547890
5 neel chennai tn 8301456987
and when my input chnages-
student_id name city state mobile
1 suraj indore m.p. 9874561230
And my output should be like-
surr_key student_id name city state mobile insert_Date end_date Flag
1 1 suraj bhopal m.p.9874561230 31/06/2015 1/09/2015 N
2 1 suraj indore m.p.9874561230 2/09/2015 31/12/9999 Y
Can anyone help me how can I do that?
You can do this with the use of trigger ,you can create before insert trigger on your target table which will update flag column of your source table.
Or you can have after update trigger on source table which will insert record in your target table.
Hope this helps
Regards,
So this should be the outline of your procedure steps. I used different columns in source and target for simplification.
Source (tu_student) - STUDENT_ID, NAME, CITY
Target (tu_student_tgt)- SKEY, STUDENT_ID, NAME, CITY, INSERT_DATE, END_DATE, IS_ACTIVE
The basic idea here is
Find the new records from source which are missing in target and Insert it. Set start_date as sysdate, end_date as 9999 and IsActive to 1.
Find the records which are updated (like your Bhopal -> Indore case). So we have to do 2 operations in target for it
Update the record in target and set end date as sysdate and IsActive to 0.
Insert this record in target which has new values. Set start_date as sysdate, end_date as 9999 and IsActive = 1.
-- Create a new oracle sequence (test_utsav_seq in this example)
---Step 1 - Find new inserts (records present in source but not in target
insert into tu_student_tgt
(
select
test_utsav_seq.nextval as skey,
s.student_id as student_id,
s.name as name,
s.city as city,
sysdate as insert_date,
'31-DEC-9999' as end_date,
1 as Flag
from tu_student s
left outer join
tu_student_tgt t
on s.student_id=t.student_id
where t.student_id is null)
----Step 2 - Find skey which needs to be updated due to data chage from source and target. So get the active records from target and compare with source data. If mismatch found, we need to
-- a update this recods in target and mark it as Inactive.
-- b Insert a new record for same student_id with new data and mark it Active.
-- part 2a - find updates.
--these records need update. Save these skey and use it one by one while updating.
select t.skey
from tu_student s inner join
tu_student_tgt t
on s.student_id=t.student_id
where t.Flag = 1 and
(s.name!=t.name or
s.city!=t.city)
--2 b ) FInd the ids which needs to be inserted as they changed in source from target. Now as above records are marked inactive,
select s.student_id
from tu_student s inner join
tu_student_tgt t
on s.student_id=t.student_id
where t.Flag = 1 and
(s.name!=t.name or
s.city!=t.city)
---2a - Implement update
-- Now use skey from 2a in a loop and run update statements like below. Replace t.key = with the keys which needs to be updated.
update tu_student_tgt t
set t.student_id = (select s.student_id from tu_student s,tu_student_tgt t where s.student_id=t.student_id and t.key= -- id from 2a step . )
, t.name=(select s.name from tu_student s,tu_student_tgt t where s.student_id=t.student_id and t.key= --id from 2a step. )
, end_date = sysdate
, is_active = 0
where t.skey = -- id from 2a step
---2b Implement Insert use student_id found in 2a
--Insert these student id like step 1
insert into tu_student_tgt
(
select
test_utsav_seq.nextval as skey,
s.student_id as student_id,
s.name as name,
s.city as city,
sysdate as insert_date,
'31-DEC-9999' as end_date,
1 as Flag
from tu_student s
where s.student_id = -- ID from 2b step - Repeat for other ids
I cannot give you a simple example of SCD-2. If you understand SCD-2, you should understand this implementation.
i have problem with this case, i have log table that has many same ID with diferent condition. i want to select two max condition from this. i've tried but it just show one record only, not every record in table.
Here's my records table:
order_id seq status____________________
1256 2 4
1256 1 2
1257 0 2
1257 3 1
Here my code:
WITH t AS(
SELECT x.order_id
,MAX(y.seq) AS seq2
,MAX(y.extern_order_status) AS status
FROM t_order_demand x
JOIN t_order_log y
ON x.order_id = y.order_id
where x.order_id like '%12%'
GROUP BY x.order_id)
SELECT *
FROM t
WHERE (t.seq2 || t.status) IN (SELECT MAX(tt.seq2 || tt.status) FROM t tt);
this query works, but sometime it gave wrong value or just show some records, not every records.
i want the result is like this:
order_id seq2 status____________________
1256 2 4
1257 3 2
I think you just want an aggregation:
select d.order_id, max(l.seq2) as seq2, max(l.status) as status
from t_order_demand d join
t_order_log l
on d.order_id = l.order_id
where d.order_id like '%12%'
group by d.order_id;
I'm not sure what your final where clause is supposed to do, but it appears to do unnecessary filtering, compared to what you want.