From the below table i want to write a select statement where i can select the price of the items for the
latest date.
Item | Price | Date
------|----------|--------
1001 | 10 | 26-5-2019
1001 | 11 | 15-02-2020
1001 | 9 | 28-08-2020
1002 | 5 | 1/7/2019
1002 | 3 | 8/11/2019
1002 | 4 | 5/5/2020
1003 | 6 | 26-05-2019
1003 | 7 | 1/2/2020
1003 | 5 | 15-09-2020
Result should be as below:
Item | Price | Date
------|----------|--------
1001 | 9 | 28-08-2020
1002 | 4 | 5/5/2020
1003 | 5 | 15-09-2020
Despite the fact that the table is unreadable and you haven't posted anything about what you have tried so far, I will try to help you...
You can get the price via Window Functions - in this case row_number. You should try something like the following:
SELECT x.*
FROM (SELECT Item, Price, [Date], ROW_NUMBER() OVER (PARTITION BY Item ORDER BY [Date] DESC) AS rn) x
WHERE x.rn = 1
Related
I've got a long table that tracks a numerical 'state' value (0=new, 1=setup mode, 2=retired, 3=active, 4=inactive) of a collection of 'devices' historically. These devices may be activated/deactivated throughout the year, so the table is continuous collection of state changes - mostly state 3 and 4, ordered by id, with a timestamp on the end, for example:
id | device_id | new_state | when
----------+-----------+-----------+----------------------------
218010581 | 2505 | 0 | 2022-06-06 16:28:11.174084
218010580 | 2505 | 1 | 2022-06-06 16:28:11.174084
218010634 | 2505 | 3 | 2022-06-06 16:29:25.129019
218087737 | 659 | 3 | 2022-06-07 22:55:48.705208
218087744 | 1392 | 3 | 2022-06-07 22:55:59.016974
218087757 | 1556 | 3 | 2022-06-07 22:56:09.811876
218087758 | 2071 | 1 | 2022-06-07 22:56:20.850095
218087765 | 2071 | 3 | 2022-06-07 22:56:29.122074
When I want to look for a list of devices and see their 'history', I know I can use something like:
select *
from devstatechange
where device_id = 2345
order by "when";
id | device_id | new_state | when
-----------+-----------+-----------+----------------------------
184682659 | 2345 | 0 | 2021-05-27 17:03:36.894429
184682658 | 2345 | 1 | 2021-05-27 17:03:36.894429
184684721 | 2345 | 3 | 2021-05-27 17:31:01.968314
194933399 | 2345 | 4 | 2021-08-31 23:30:05.555407
195213746 | 2345 | 3 | 2021-09-03 16:53:39.043005
206278232 | 2345 | 4 | 2021-12-31 22:30:08.820068
206515355 | 2345 | 3 | 2022-01-03 16:06:01.223759
215709888 | 2345 | 4 | 2022-04-30 23:30:30.309389
215846807 | 2345 | 3 | 2022-05-02 19:40:31.525514
select *
from devstatechange
where device_id = 2351
order by "when";
id | device_id | new_state | when
-----------+-----------+-----------+----------------------------
186091252 | 2351 | 0 | 2021-06-09 15:36:02.775035
186091253 | 2351 | 1 | 2021-06-09 15:36:02.775035
186091349 | 2351 | 3 | 2021-06-09 15:37:56.965599
197880878 | 2351 | 4 | 2021-09-30 23:30:06.691835
197945073 | 2351 | 3 | 2021-10-01 15:32:35.907913
208981857 | 2351 | 4 | 2022-01-31 22:30:09.521694
209722639 | 2351 | 3 | 2022-02-09 15:20:12.412816
217666572 | 2351 | 4 | 2022-05-31 23:30:30.881928
What I am really looking for is a query that returns a unique list of devices where the latest dated entry for each device only contains a state of '4' ('inactive state'), and not include records that do not match.
So in using the above data samples, even though both devices 2345 and 2351 have states of 3 and 4 throughout their history, only device 2351 has it's last dated entry with a state of 4 - meaning it is currently in an 'inactive' state. Device 2345's would not appear in the result set since its last dated entry has a state of 3 - it's still active.
Stabbing in the dark, I've tried variants of:
SELECT DISTINCT *
FROM devstatechange
WHERE MAX("when") AND new_state = 4
ORDER BY "when";
SELECT DISTINCT device_id, new_state, MAX("when")
FROM devstatechange
WHERE new_state = 4
ORDER BY "when";
with obviously no success.
I'm thinking I might need to 'group' the entries together, but I don't know how to specify 'return last entry only if new_state = 4' in SQL, or rather PostgreSQL.
Any tidbits or pokes in the right direction would be appreciated.
SELECT * FROM (
SELECT DISTINCT ON (device_id)
*
FROM devstatechange
ORDER BY device_id, "when" DESC
) AS latest
WHERE new_state = 4;
The DISTINCT ON keyword together with the ORDER BY will pull the newest row for each device. The outer query then filters these by your condition.
You may use Row_Number() function with a partition by device_id and order by when.
Try the following CTE:
with cte as
(
Select id ,device_id ,new_state ,when_ ,
row_number() over (partition by device_id order by when_ desc) as rn
from devstatechange
)
select * from cte where rn=1 and new_state=4
See a demo from db-fiddle.
The problem with:
SELECT DISTINCT * FROM devstatechange WHERE MAX("when") AND new_state=4 ORDER BY "when";
is that MAX("when") refers to all the entrys on the table.
you should change it to:
when = (select max(when) from devstatechange dev2 where dev2.device_id = dev1.device_id )
You can use CTE to obtain a last state of each device and then select only those, whose last state is 4, like this
WITH device_last_state AS (
SELECT DISTINCT ON (device_id)
id,
device_id,
last_value (new_state) over (partition by device_id order by "when" desc) as new_state,
"when"
FROM devicestatechange
)
SELECT * FROM device_last_state
WHERE new_state = 4
Check a demo
I have a table of items in the shop, an item may have different entries with same serial number (sn) (but different ids) if the same item was bought again later on with different price (price here is how much did a single item cost the shop)
id | sn | amount | price
----+------+--------+-------
1 | AP01 | 100 | 7
2 | AP01 | 50 | 8
3 | X2P0 | 200 | 12
4 | X2P0 | 30 | 18
5 | STT0 | 20 | 20
6 | PLX1 | 200 | 10
and a table of transactions
id | item_id | price
----+---------+-------
1 | 1 | 10
2 | 1 | 9
3 | 1 | 10
4 | 2 | 11
5 | 3 | 15
6 | 3 | 15
7 | 3 | 15
8 | 4 | 18
9 | 5 | 22
10 | 5 | 22
11 | 5 | 22
12 | 5 | 22
and transaction.item_id references items(id)
I want to group items by serial number (sn), get their sum(amount) and avg(price), and join it with a sold column that counts number of transactions with referenced id
I did the first with
select i.sn, sum(i.amount), avg(i.price) from items i group by i.sn;
sn | sum | avg
------+-----+---------------------
STT0 | 20 | 20.0000000000000000
PLX1 | 200 | 10.0000000000000000
AP01 | 150 | 7.5000000000000000
X2P0 | 230 | 15.0000000000000000
Then when I tried to join it with transactions I got strange results
select i.sn, sum(i.amount), avg(i.price) avg_cost, count(t.item_id) sold, sum(t.price) profit from items i left join transactions t on (i.id=t.item_id) group by i.sn;
sn | sum | avg_cost | sold | profit
------+-----+---------------------+------+--------
STT0 | 80 | 20.0000000000000000 | 4 | 88
PLX1 | 200 | 10.0000000000000000 | 0 | (null)
AP01 | 350 | 7.2500000000000000 | 4 | 40
X2P0 | 630 | 13.5000000000000000 | 4 | 63
As you can see, only the sold and profit columns show correct results, the sum and avg show different results than the expected
I can't separate the statements because I am not sure how can I add the count to the sn group which has the item_id as its id?
select
j.sn,
j.sum,
j.avg,
count(item_id)
from (
select
i.sn,
sum(i.amount),
avg(i.price)
from items i
group by i.sn
) j
left join transactions t
on (j.id???=t.item_id);
There are multiple matches in both tables, so the join multiplies the rows (and eventually produces wron results). I would recommend pre-joining, then aggregating:
select
sn,
sum(amount) total_amount,
avg(price) avg_price,
sum(no_transactions) no_transactions
from (
select
i.*,
(
select count(*)
from transactions t
where t.item_id = i.id
) no_transactions
from items i
) t
group by sn
I've been stuck on this question for a while, and I was wondering if the community would be able to direct me in the right direction?
I have some tag IDs that needs to be grouped, with exceptions (column: deleted) that need to be retained in the results. After which, for each grouped tag ID, I need to select the one with the latest date. How can I do this? An example below:
ID | TAG_ID | DATE | DELETED
1 | 300 | 05/01/20 | null
2 | 300 | 03/01/20 | 04/01/20
3 | 400 | 06/01/20 | null
4 | 400 | 05/01/20 | null
5 | 400 | 04/01/20 | null
6 | 500 | 03/01/20 | null
7 | 500 | 02/01/20 | null
I am trying to reach this outcome:
ID | TAG_ID | DATE | DELETED
1 | 300 | 05/01/20 | null
2 | 300 | 03/01/20 | 04/01/20
3 | 400 | 06/01/20 | null
6 | 500 | 03/01/20 | null
So, firstly if there is a date in the "DELETED" column, I would like the row to be present. Secondly, for each unique tag ID, I would like the row with the latest "DATE" to be present.
Hopefully this question is clear. Would appreciate your feedback and help! A big thanks in advance.
Your results seem to be something like this:
select t.*
from (select t.*,
row_number() over (partition by tag_id, deleted order by date desc) as seqnum
from t
) t
where seqnum = 1 or deleted is not null;
This takes one row where deleted is null -- the most recent row. It also keeps each row where deleted is not null.
You need 2 conditions combined with OR in the WHERE clause:
the 1st is deleted is not null, or
the 2nd that there isn't any other row with the same tag_id and date later than the current row's date, meaning that the current row's date is the latest:
select t.* from tablename t
where t.deleted is not null
or not exists (
select 1 from tablename
where tag_id = t.tag_id and date > t.date
)
See the demo.
Results:
| id | tag_id | date | deleted |
| --- | ------ | ---------- | -------- |
| 1 | 300 | 2020-05-01 | |
| 2 | 300 | 2020-03-01 | 04/01/20 |
| 3 | 400 | 2020-06-01 | |
| 6 | 500 | 2020-03-01 | |
I'm attempting to combine multiple rows using a UNION but I need to pull in additional data as well. My thought was to use a UNION in the outer query but I can't seem to make it work. Or am I going about this all wrong?
The data I have is like this:
+------+------+-------+---------+---------+
| ID | Time | Total | Weekday | Weekend |
+------+------+-------+---------+---------+
| 1001 | AM | 5 | 5 | 0 |
| 1001 | AM | 2 | 0 | 2 |
| 1001 | AM | 4 | 1 | 3 |
| 1001 | AM | 5 | 3 | 2 |
| 1001 | PM | 5 | 3 | 2 |
| 1001 | PM | 5 | 5 | 0 |
| 1002 | PM | 4 | 2 | 2 |
| 1002 | PM | 3 | 3 | 0 |
| 1002 | PM | 1 | 0 | 1 |
+------+------+-------+---------+---------+
What I want to see is like this:
+------+---------+------+-------+
| ID | DayType | Time | Tasks |
+------+---------+------+-------+
| 1001 | Weekday | AM | 9 |
| 1001 | Weekend | AM | 7 |
| 1001 | Weekday | PM | 8 |
| 1001 | Weekend | PM | 2 |
| 1002 | Weekday | PM | 5 |
| 1002 | Weekend | PM | 3 |
+------+---------+------+-------+
The closest I've come so far is using UNION statement like the following:
SELECT * FROM
(
SELECT Weekday, 'Weekday' as 'DayType' FROM t1
UNION
SELECT Weekend, 'Weekend' as 'DayType' FROM t1
) AS X
Which results in something like the following:
+---------+---------+
| Weekday | DayType |
+---------+---------+
| 2 | Weekend |
| 0 | Weekday |
| 2 | Weekday |
| 0 | Weekend |
| 10 | Weekday |
+---------+---------+
I don't see any rhyme or reason as to what the numbers are under the 'Weekday' column, I suspect they're being grouped somehow. And of course there are several other columns missing, but since I can't put a large scope in the outer query with this as inner one, I can't figure out how to pull those in. Help is greatly appreciated.
It looks like you want to union all a pair of aggregation queries that use sum() and group by id, time, one for Weekday and one for Weekend:
select Id, DayType = 'Weekend', [time], Tasks=sum(Weekend)
from t
group by id, [time]
union all
select Id, DayType = 'Weekday', [time], Tasks=sum(Weekday)
from t
group by id, [time]
Try with this
select ID, 'Weekday' as DayType, Time, sum(Weekday)
from t1
group by ID, Time
union all
select ID, 'Weekend', Time, sum(Weekend)
from t1
group by ID, Time
order by order by 1, 3, 2
Not tested, but it should do the trick. It may require 2 proc sql steps for the calculation, one for summing and one for the case when statements. If you have extra lines, just use a max statement and group by ID, Time, type_day.
Proc sql; create table want as select ID, Time,
sum(weekday) as weekdayTask,
sum(weekend) as weekendTask,
case when calculated weekdaytask>0 then weekdaytask
when calculated weekendtask>0 then weekendtask else .
end as Task,
case when calculated weekdaytask>0 then "Weekday"
when calculated weekendtask>0 then "Weekend"
end as Day_Type
from have
group by ID, Time
;quit;
Proc sql; create table want2 as select ID, Time, Day_Type, Task
from want
;quit;
I need to retrieve the records from dbo.transaction (transaction of all users-more than one transaction for each user) that having timestamp which is closest to the time in dbo.bal (current balance details of each user-only one record for each user)
ie, the resultant records should equal to the no of records in the dbo.bal
Here i tried the below query, am getting only the records less than the time in dbo.bal. But there are some record having timestamp greater than and closest to dbo.bal.time
SELECT dbo.bal.uid,
dbo.bal.userId,
dbo.bal.balance,
dbo.bal.time,
(SELECT TOP 1 transactionBal
FROM dbo.transaction
WHERE TIMESTAMP <= dbo.bal.time
ORDER BY TIMESTAMP DESC) AS newBal
FROM dbo.bal
WHERE dbo.bal.time IS NOT NULL
ORDER BY dbo.bal.time DESC
here is my table structure,
dbo.transaction
---------------
| uid| userId | description| timestamp | credit | transactionBal
-------------------------------------------------------------------------
| 1 | 101 | buy credit1| 2012-01-25 03:23:31.624 | 100 | 500
| 2 | 102 | buy credit5| 2012-01-18 03:13:12.657 | 500 | 700
| 3 | 103 | buy credit3| 2012-01-15 02:16:34.667 | 300 | 300
| 4 | 101 | buy credit2| 2012-01-13 05:34:45.637 | 200 | 300
| 5 | 101 | buy credit1| 2012-01-12 07:45:21.457 | 100 | 100
| 6 | 102 | buy credit2| 2012-01-01 08:18:34.677 | 200 | 200
dbo.bal
-------
| uid| userId | balance | time |
-----------------------------------------------------
| 1 | 101 | 500 | 2012-01-13 05:34:45.645 |
| 2 | 102 | 700 | 2012-01-01 08:18:34.685 |
| 3 | 103 | 300 | 2012-01-15 02:16:34.672 |
And the result should be like,
| Id | userId | balance | time | credit | transactionBal
-----------------------------------------------------------------------------
| 1 | 101 | 500 | 2012-01-13 05:34:45.645 | 200 | 300
| 2 | 102 | 700 | 2012-01-01 08:18:34.685 | 200 | 200
| 3 | 103 | 300 | 2012-01-15 02:16:34.672 | 300 | 300
Please help me.. Any help is must appreciated...Thankyou
It would be helpful if you posted your table structures, but ...
I think your inner query needs a join condition. (That is not actually in your question)
Your ORDER BY clause in the inner query could be ABS(TIMESTAMP - DB0.BAL.TIME). That should give you the smallest difference between the 2.
Does that help ?
Based on the follwing Sql Fiddle http://sqlfiddle.com/#!3/7a900/15 I came up with ...
SELECT
bal.uid,
bal.userId,
bal.balance,
bal.time,
trn.timestamp,
trn.description,
datediff(ms, bal.time, trn.timestamp)
FROM
money_balances bal
JOIN money_transaction trn on
trn.userid = bal.userid and
trn.uid =
(
select top 1 uid
from money_transaction trn2
where trn2.userid = trn.userid
order by abs(datediff(ms, bal.time, trn2.timestamp))
)
WHERE
bal.time IS NOT NULL
ORDER BY
bal.time DESC
I cannot vouch for its performance because I know nothing of your data, but I believe it works.
I have simplified my answer - I believe what you need is
SELECT
bal.uid as baluid,
(
select top 1 uid
from money_transaction trn2
where trn2.userid = bal.userid
order by abs(datediff(ms, bal.time, trn2.timestamp))
) as tranuid
FROM
money_balances bal
and from that you can derive all the datasets you need.
for example :
with matched_credits as
(
SELECT
bal.uid as baluid,
(
select top 1 uid
from money_transaction trn2
where trn2.userid = bal.userid
order by abs(datediff(ms, bal.time, trn2.timestamp))
) as tranuid
FROM
money_balances bal
)
select
*
from
matched_credits mc
join money_balances mb on
mb.uid = mc.baluid
join money_transaction trn on
trn.uid = mc.tranuid
Try:
SELECT dbo.bal.uid,
dbo.bal.userId,
dbo.bal.balance,
dbo.bal.time,
(SELECT TOP 1 transactionBal
FROM dbo.transaction
ORDER BY abs(datediff(ms, dbo.bal.time, TIMESTAMP))) AS newBal
FROM dbo.bal
WHERE dbo.bal.time IS NOT NULL
ORDER BY dbo.bal.time DESC