SQL SELECT multiple max values for a date - sql

Question

I am trying to get the latest record from a table by filtering a column with max, but it looks like I have multiple records for the same max date. I have added an ORDER BY at the end of the query and looks like I can actually retrieve the latest value since it has a correct order, but i don't know how.
Below you will find a descriptive image:
Also please find below the query that I am using:
SELECT *
FROM item_forecast_detail
WHERE item_id = 177010 AND
forecast_dt = (SELECT MAX(forecast_dt)
FROM item_forecast_detail
WHERE item_id = 177010)
ORDER BY forecast_dt DESC

Answer 1

One option is to apply another condition, e.g. fetch the latest starting_hour:
SQL> with item_forecast_Detail (item_id, forecast_dt, starting_hour) as
2 (select 177010, date '2019-07-07', 21 from dual union all
3 select 177010, date '2019-07-07', 18 from dual union all
4 select 177010, date '2019-07-07', 15 from dual union all
5 select 177010, date '2019-07-07', 12 from dual union all
6 --
7 select 123456, date '2019-02-17', 09 from dual
8 )
9 select *
10 from item_forecast_Detail i
11 where i.item_id = 177010
12 and i.forecast_dt = (select max(i1.forecast_dt)
13 from item_forecast_detail i1
14 where i1.item_id = i.item_id
15 )
16 and i.starting_hour = (select max(i2.starting_hour)
17 from item_forecast_detail i2
18 where i2.item_id = i.item_id
19 );
ITEM_ID FORECAST_D STARTING_HOUR
---------- ---------- -------------
177010 07.07.2019 21
SQL>
Another one is to sort them by using analytical function and apply it to the final query:
SQL> with item_forecast_Detail (item_id, forecast_dt, starting_hour) as
2 (select 177010, date '2019-07-07', 21 from dual union all
3 select 177010, date '2019-07-07', 18 from dual union all
4 select 177010, date '2019-07-07', 15 from dual union all
5 select 177010, date '2019-07-07', 12 from dual union all
6 --
7 select 123456, date '2019-02-17', 09 from dual
8 ),
9 sort as
10 (select i.*,
11 row_number() over (partition by item_id order by forecast_dt, starting_hour desc) rn
12 from item_forecast_Detail i
13 )
14 select *
15 from sort s
16 where s.item_id = 177010
17 and s.rn = 1;
ITEM_ID FORECAST_D STARTING_HOUR RN
---------- ---------- ------------- ----------
177010 07.07.2019 21 1
SQL>

Answer 2

Use row_number() window analytic function to order as desired, and max(forecast_dt) over (order by forecast_dt desc) to detect the latest date
SELECT *
FROM
(
SELECT d.*,
row_number() over (order by ending_hour desc) as rn,
max(forecast_dt) over (order by forecast_dt desc) as mx
FROM item_forecast_detail d
WHERE item_id=177010
)
WHERE mx = forecast_dt
ORDER BY rn

Answer 3

You could try this with MySQL, SQLServer:
SELECT * FROM TABLE ORDER BY FORECAST_DT DESC LIMIT 1
SELECT TOP 1 * FROM Table ORDER BY FORECAST_DT DESC

Answer 4

You can use ROWNUM.
-- FETCH MAX FOR SINGLE item_id
WITH item_forecast_detail(item_id, forecast_dt, SOME_OTHER_COLS) AS (
SELECT 177010, DATE '2019-07-01','ANY VALUE - 1' FROM DUAL UNION ALL
SELECT 177010, DATE '2019-07-01','ANY VALUE - 2' FROM DUAL UNION ALL
SELECT 177010, DATE '2019-07-02','ANY VALUE - 4' FROM DUAL UNION ALL
SELECT 177010, DATE '2019-07-02','ANY VALUE - 5' FROM DUAL UNION ALL
SELECT 177010, DATE '2019-07-02','ANY VALUE - 6' FROM DUAL UNION ALL
SELECT 177011, DATE '2019-07-01','ANY VALUE - 1' FROM DUAL UNION ALL
SELECT 177011, DATE '2019-07-01','ANY VALUE - 1' FROM DUAL UNION ALL
SELECT 177011, DATE '2019-06-30','ANY VALUE - 1' FROM DUAL
)
SELECT
ITEM_ID,
FORECAST_DT,
SOME_OTHER_COLS
FROM
(
SELECT
ITEM_ID,
FORECAST_DT,
SOME_OTHER_COLS,
ROW_NUMBER() OVER(
PARTITION BY ITEM_ID
ORDER BY
FORECAST_DT DESC
) AS RN
FROM
ITEM_FORECAST_DETAIL
WHERE
ITEM_ID = 177010
)
WHERE
RN = 1
OUTPUT
-- FETCH MAX FOR MULTIPLE item_id
WITH item_forecast_detail(item_id, forecast_dt, SOME_OTHER_COLS) AS (
SELECT 177010, DATE '2019-07-01','ANY VALUE - 1' FROM DUAL UNION ALL
SELECT 177010, DATE '2019-07-01','ANY VALUE - 2' FROM DUAL UNION ALL
SELECT 177010, DATE '2019-07-02','ANY VALUE - 4' FROM DUAL UNION ALL
SELECT 177010, DATE '2019-07-02','ANY VALUE - 5' FROM DUAL UNION ALL
SELECT 177010, DATE '2019-07-02','ANY VALUE - 6' FROM DUAL UNION ALL
SELECT 177011, DATE '2019-07-01','ANY VALUE - 1' FROM DUAL UNION ALL
SELECT 177011, DATE '2019-07-01','ANY VALUE - 1' FROM DUAL UNION ALL
SELECT 177011, DATE '2019-06-30','ANY VALUE - 1' FROM DUAL
)
SELECT
ITEM_ID,
FORECAST_DT,
SOME_OTHER_COLS
FROM
(
SELECT
ITEM_ID,
FORECAST_DT,
SOME_OTHER_COLS,
ROW_NUMBER() OVER(
PARTITION BY ITEM_ID
ORDER BY
FORECAST_DT DESC
) AS RN
FROM
ITEM_FORECAST_DETAIL
--WHERE item_id = 177010
)
WHERE
RN = 1
OUTPUT
DB<>FIDDLE DEMO
Cheers!!