I am trying to use the lag function so I can compare one column to the last without using a cursor.
However the column I need to compare against has to go by an alias as I am using 3 unions).
Here is an example of what I am up to.
SELECT
'Y' AS paid,
lag(paid,1) over (ORDER BY salary) AS prev_paid
FROM pay
UNION
SELECT
'N' as paid,
lag(paid,1) over (ORDER BY salary) AS prev_paid
FROM not_paid
I keep getting the Error: PL/SQL: ORA-00904: "paid": invalid identifier
I suspect you want something more like this:
SELECT paid, lag(paid,1) over (ORDER BY salary) AS prev_paid
FROM
(
SELECT 'Y' as paid, salary
FROM pay
UNION
SELECT 'N' as paid, salary
FROM not_paid
)
The general answer is no: in Oracle you can never use a column alias at the level where it is defined, except in order by clauses.
However, your query has other issues, since you're getting the lag value of a constant. #Tony Andrew's query seems like what you actually want.
Related
I don't understand , why I am taking this error.
SELECT
to_char(view_date, 'Month') MONAT ,
COUNT(*) AS countx
FROM
AXY_TABLE
GROUP BY
to_char(view_date,'Month')
ORDER BY
to_char(view_date, 'Month'),
COUNT(*) desc;
When I execute this Query for a Interactive Report, it throws ORA-01722 Error. This Query run not only correctly in SQL developer but also as Classic Report correctly. When I changed the type to Interactive Report, throws it again the same error.
What should I do ?
Thanks a lot in advance.
Is the problem the ORDER BY clause? Try removing the aggregation from it:
SELECT
to_char(view_date, 'Month') MONAT ,
COUNT(*) AS countx
FROM
AXY_TABLE
GROUP BY
to_char(view_date,'Month')
ORDER BY
to_char(view_date, 'Month'),
2 desc;
This orders by the position of the second column of the projection. However, it is strictly unnecessary, as your result set will conatin only one row per MONTH, so you only need to sort by that.
Just had a user answer this correctly for TSQL, but wondering how best to achieve this now in SQL Developer/PLSQL seeing as there is no DATEDIFF function.
Table I want to query on has some 'CODE' values, which can naturally have multiple primary key records ('OccsID') in a table 'Occs'. There is also a datetime column called 'CreateDT' for each OccsID.
Just want to find the maximum possible time variance between any 2 consecutive rows in 'Occs', per 'CODE'.
If you subtract the "next" date and "this" date (using the LEAD analytic function), you'll get the date difference. Then fetch the maximum difference per code. Something like this:
with diff as
(select occsid,
code,
nvl(lead(createdt) over (partition by code order by createdt), createdt) - createdt date_diff
from test
)
select code,
max(date_diff)
from diff
group by code;
Assuming that this T-SQL version works for you (from the prior question)
SELECT x.code, MAX(x.diff_sec) FROM
(
SELECT
code,
DATEDIFF(
SECOND,
CreateDT,
LEAD(CreateDT) OVER(PARTITION BY CODE ORDER BY CreateDT) --next row's createdt
) as diff_sec
FROM Occs
)x
GROUP BY x.code
The simplest option is just to subtract the two dates to get a difference in days. You can then multiply to get the difference in hours, minutes, or seconds
SELECT x.code, MAX(x.diff_day), MAX(x.diff_sec)
FROM
(
SELECT
code,
CreateDT -
LEAD(CreateDT) OVER(PARTITION BY CODE ORDER BY CreateDT) as diff_day,
24*60*60* (CreateDT -
LEAD(CreateDT) OVER(PARTITION BY CODE ORDER BY CreateDT)) as diff_sec
FROM Occs
)x
GROUP BY x.code
i have a select(water readings, previous water reading, other columns) , a "where clause" that is based on date water reading date. however for previous water reading it must not consider the where clause. I want to get previous meter reading regardless where clause date range.
looked at union problem is that i have to use the same clause,
SELECT
WATERREADINGS.name,
WATERREADINGS.date,
LAG( WATERREADINGS.meter_reading,1,NULL) OVER(
PARTITION BY WATERREADINGS.meter_id,WATERREADINGS.register_id
ORDER BY WATERREADINGS.meter_id DESC,WATERREADINGS.register_id
DESC,WATERREADINGS.readingdate ASC,WATERREADINGS.created ASC
) AS prev_water_reading,
FROM WATERREADINGS
WHERE waterreadings.waterreadingdate BETWEEN '24-JUN-19' AND
'24-AUG-19' and isactive = 'Y'
The prev_water_reading value must not be restricted by the date BETWEEN '24-JUN-19' AND '24-AUG-19' predicate but the rest of the sql should be.
You can do this by first finding the previous meter readings for all rows and then filtering those results on the date, e.g.:
WITH meter_readings AS (SELECT waterreadings.name,
waterreadings.date dt,
lag(waterreadings.meter_reading, 1, NULL) OVER (PARTITION BY waterreadings.meter_id, waterreadings.register_id
ORDER BY waterreadings.readingdate ASC, waterreadings.created ASC)
AS prev_water_reading,
FROM waterreadings
WHERE isactive = 'Y')
-- the meter_readings subquery above gets all rows and finds their previous meter reading.
-- the main query below then applies the date restriction to the rows from the meter_readings subquery.
SELECT name,
date,
prev_water_reading,
FROM meter_readings
WHERE dt BETWEEN to_date('24/06/2019', 'dd/mm/yyyy') AND to_date('24/08/2019', 'dd/mm/yyyy');
Perform the LAG in an inner query that is not filtered by dates and then filter by the dates in the outer query:
SELECT name,
"date",
prev_water_reading
FROM (
SELECT name,
"date",
LAG( meter_reading,1,NULL) OVER(
PARTITION BY meter_id, register_id
ORDER BY meter_id DESC, register_id DESC, readingdate ASC, created ASC
) AS prev_water_reading,
waterreadingdate --
FROM WATERREADINGS
WHERE isactive = 'Y'
)
WHERE waterreadingdate BETWEEN DATE '2019-06-24' AND DATE '2019-08-24'
You should also not use strings for dates (that require an implicit cast using the NLS_DATE_FORMAT session parameter, which can be changed by any user in their own session) and use date literals DATE '2019-06-24' or an explicit cast TO_DATE( '24-JUN-19', 'DD-MON-RR' ).
You also do not need to reference the table name for every column when there is only a single table as this clutters up your code and makes it difficult to read and DATE is a keyword so you either need to wrap it in double quotes to use it as a column name (which makes the column name case sensitive) or should use a different name for your column.
I've added a subquery with previous result without filter and then joined it with the main table with filters:
SELECT
WATERREADINGS.name,
WATERREADINGS.date,
w_lag.prev_water_reading
FROM
WATERREADINGS,
(SELECT name, date, LAG( WATERREADINGS.meter_reading,1,NULL) OVER(
PARTITION BY WATERREADINGS.meter_id,WATERREADINGS.register_id
ORDER BY WATERREADINGS.meter_id DESC,WATERREADINGS.register_id
DESC,WATERREADINGS.readingdate ASC,WATERREADINGS.created ASC
) AS prev_water_reading
FROM WATERREADINGS) w_lag
WHERE waterreadings.waterreadingsdate BETWEEN '24-JUN-19' AND '24-AUG-19' and isactive = 'Y'
and WATERREADINGS.name = w_lag.name
and WATERREADINGS.date = w_lag.date
I don't often use ORACLE PL/SQL by the way but i need to understand what if anything in this function created by someone else
in the company before me is wrong as for it is not returning the latest record i've been told. I found out in some other forum issues that they
suggested to use the max(dateColumn) instead of "row_numer = 1" for example but not quite sure how to and where to incorporate that.
-- Knowing that --
We use Oracle version 12,
CustomObjectTypeA is an custom Oracle OBJECT TYPE defined by some old employee not longer in here,
V_OtherView is of Table_Mnd type beeing defined by some old employee not longer in here,
V_ABC_123 is a view created by some old employee not longer in here as well.
CREATE OR REPLACE FUNCTION F_TABLE_APPROVED (NUMBER_F_UPD number, NUMBER_F_GET VARcHAR2)
RETURN Table_Mnd
IS
V_OtherView Table_Mnd
BEGIN
SELECT CustomObjectTypeA (FromT.NUMBER_F,
FromT.OP_CODE,
FromT.CATG_CODE,
FromT.CATG_NAME,
FromT.CATG_SORT,
FromT.ORG_CODE,
FromT.ORG_NAME
FromT.DATA_ENTRY_VALID,
FromT.NUMBER_RECEIVED,
FromT.YEAR_1,
FromT.YEAR_2)
BULK COLLECT INTO V_OtherView
FROM (SELECT NUMBER_F,
OP_CODE,
CATG_CODE,
CATG_NAME,
CATG_SORT,
ORG_CODE,
ORG_NAME
DATA_ENTRY_VALID,
NUMBER_RECEIVED,
YEAR_1,
YEAR_2,
ROW_NUMBER() OVER (PARTITION BY BY ORG_CODE ORDER BY NUMBER_RECEIVED DESC, LOAD_DATE DESC) AS ROW_NUMBER
FROM V_ABC_123
WHERE NUMBER_F = NUMBER_F_UPD AND DATA_ENTRY_VALID <> 'OnGoing'
AND LOAD_DATE >= (SELECT sysdate-10 FROM dual)
AND LOAD_DATE <= (SELECT DISTINCT LOAD_DATE
FROM V_ABC_123
WHERE NUMBER_RECEIVED = NUMBER_F_GET)) FromT
WHERE FromT.ROW_NUMBER=1;
RETURN V_OtherView;
END F_TABLE_APPROVED;
The important bits of the query are:
SELECT ...
FROM (select ...,
ROW_NUMBER()
OVER (PARTITION BY ORG_CODE
ORDER BY NUMBER_RECEIVED DESC,
LOAD_DATE DESC) AS ROW_NUMBER
...) FromT
WHERE FromT.ROW_NUMBER = 1;
The "ROW_NUMBER" column is computed according to the following window clause:
PARTITION BY ORG_CODE
ORDER BY NUMBER_RECEIVED DESC, LOAD_DATE DESC
Which means that for each ORG_CODE, it will sort all the records by NUMBER_RECEVED,LOAD_DATE in descending order. Note that if the columns are Oracle DATEs, they will only be accurate to the nearest second; so if there are multiple records with date/times in the exact same 1-second interval, this sort order will not be guaranteed unique. The logic of ROW_NUMBER will therefore pick one of them arbitrarily (i.e. whichever record happens to be emitted first) and assign it the value "1", and this will be deemed the "latest". Subsequent executions of the same SQL could (in theory) return a different record.
The suspicious part is NUMBER_RECEIVED which sounds like it's a number, not a date? Sorting by this means that the records with the highest NUMBER_RECEIVED will be preferred. Was this intentional?
I'm not sure why the PARTITION is there, this would cause the query to return one "latest" record for each value of ORG_CODE that it finds. I can only assume this was intentional.
The problem is that the query can only determine the "latest record" as well as it can based on the data provided to it. In this case, it's possible the data is simply not granular enough to be able to decide which record is the actual "latest" record.
Using Oracle, PSQL, I am trying to figure out the earliest invoice date for each supplier. That would be simple enough, but I am also trying to figure out the max distribution line on the earliest invoice so I can determine what segment of the business the invoice belongs to. Segment is determined by SEGMENT_NUMBER in the example below. I know a sub query or multiple sub queries are needed here with a group by clause but I am at a loss. The syntax below is not even close, but I wanted to provided something for feedback.
SELECT
SUPPLIER_ID,
INVOICE_NUMBER,
SEGMENT_NUMBER,
MIN(INVOICE_DATE) as EARLIEST_INV_DATE,
MAX(DISTRIBUTION_AMOUNT) as MAX_DIST_LINE
FROM INVOICE_DIST
Use Analytical function like RANK().
SELECT SUPPLIER_ID,
INVOICE_NUMBER,
SEGMENT_NUMBER,
INVOICE_DATE,DISTRIBUTION_AMOUNT
(SELECT SUPPLIER_ID,
INVOICE_NUMBER,
SEGMENT_NUMBER,
INVOICE_DATE,DISTRIBUTION_AMOUNT,
RANK() OVER(PARTITION BY SUPPLIER_ID ORDER BY INVOICE_DATE,DISTRIBUTION_AMOUNT DESC) POSITION FROM INVOICE_DIST) TBL WHERE POSITION=1;