I'm using T-SQL 2014
Suppose I have a stock price chart as follow
I want to write efficient code for a stored function to display the Open price at the start, Close price at the end, and the difference between Close and Open. Is it possible to do that in one query? The query seems easy but it turned out extremely difficult. My first problem is to display the first row and last row in one query.
My attempt is like this
create function GetVolatilityRank(#from date, #to date)
returns table as
return(
with Price_Selected_Time as (select * from Price where [date] between #from and #to)
select
(select top 1([Open]) from Price_Selected_Time) as 'Open',
(select top 1([Close]) from Price_Selected_Time order by date desc) as 'Close',
[Close] - [Open] as 'Difference'
);
I feel this code is very clumsy. And it also won't let me pass, because the 'Open'and 'Close' is not defined yet.
Is there anyway to query this in one select?
Thank you
We can handle this via a regular query using ROW_NUMBER:
WITH cte AS (
SELECT *, ROW_NUMBER() OVER (ORDER BY Date) rn_start,
ROW_NUMBER() OVER (ORDER BY Date DESC) rn_end
FROM Price
)
SELECT
MAX(CASE WHEN rn_start = 1 THEN [Open] END) AS OpenStart,
MAX(CASE WHEN rn_end = 1 THEN [Close] END) AS CloseEnd,
MAX(CASE WHEN rn_end = 1 THEN [Close] END) -
MAX(CASE WHEN rn_start = 1 THEN [Open] END) AS diff
FROM cte;
Related
I am very new to sql and query writing and after alot of trying, I am asking for help.
As shown in the picture, I want to create partition of data based on is_late = 1 and show its count (that is 2) but at the same time want to capture the value of last_status where is_late = 0 to be displayed in the single row.
The task is to calculate how many time the rider was late and time taken by him from first occurrence of estimated time to the last_status.
Desired output:
You can use following query
SELECT
rider_id,
task_created_time,
expected_time_to_arrive,
is_late,
last_status,
task_count,
CONVERT(VARCHAR(5), DATEADD(MINUTE, DATEDIFF(MINUTE, expected_time_to_arrive, last_status), 0), 114) AS time_delayed
FROM
(SELECT
rider_id,
task_created_time,
expected_time_to_arrive,
is_late,
SUM(CASE WHEN is_late = 1 THEN 1 ELSE 0 END) OVER(PARTITION BY rider_id ORDER BY rider_id) AS task_count,
ROW_NUMBER() OVER(PARTITION BY rider_id ORDER BY rider_id) AS num,
MAX(last_status) OVER(PARTITION BY rider_id ORDER BY rider_id) AS last_status
FROM myTestTable) t
WHERE num = 1
db<>fiddle
i'm new to SQL and i would need an help.
I have a TAB and I need to find for any item B in the TAB the item A with the closest date. In this case the A with 02.09.2021 04:25:30
Date.
Item
07.09.2021 05:02:05
A
06.09.2021 05:01:02
A
05.09.2021 05:00:02
A
04.09.2021 04:59:01
A
03.09.2021 04:58:03
A
02.09.2021 04:56:55
A
02.09.2021 04:33:56
B
02.09.2021 04:25:30
A
WITH CTE(DATE,ITEM)AS
(
SELECT '20210907 05:02:05' , 'A'UNION ALL
SELECT '20210906 05:01:02' , 'A'UNION ALL
SELECT '20210905 05:00:02' , 'A'UNION ALL
SELECT'20210904 04:59:01' , 'A'UNION ALL
SELECT'20210903 04:58:03' , 'A'UNION ALL
SELECT'20210902 04:56:55' , 'A'UNION ALL
SELECT'20210902 04:33:56' , 'B'UNION ALL
SELECT'20210902 04:25:30' , 'A'
)
SELECT
CAST(C.DATE AS DATETIME)X_DATE,C.ITEM,Q.CLOSEST
FROM CTE AS C
OUTER APPLY
(
SELECT TOP 1 CAST(X.DATE AS DATETIME)CLOSEST
FROM CTE AS X
WHERE X.ITEM='A'AND CAST(X.DATE AS DATETIME)<CAST(C.DATE AS DATETIME)
ORDER BY CAST(X.DATE AS DATETIME) ASC
)Q
WHERE C.ITEM='B'
You can use OUTER APPLY-approach as in the above query.
Please also take a look that datetime-column (DATE)is written in the ISO-compliant form
Your data has only two columns. If you want the only the closest A timestamp, then the fastest way is probably window functions:
select t.*,
(case when prev_a_date is null then next_a_date
when next_a_date is null then prev_a_date
when datediff(second, prev_a_date, date) <= datediff(second, date, next_a_date) then prev_a_date
else next_a_date
end) as a_date
from (select t.*,
max(case when item = 'A' then date end) over (order by date) as prev_a_date,
min(case when item = 'A' then date end) over (order by date desc) as next_a_date
from t
) t
where item = 'B';
This uses seconds to measure the time difference, but you can use a smaller unit if appropriate.
You can also do this using apply if you have more columns from the "A" rows that you want:
select tb.*, ta.*
from t b outer apply
(select top (1) ta.*
from t ta
where item = 'A'
order by abs(datediff(second, a.date, b.date))
) t
where item = 'B';
I want to make a calculation based on the excel file. I succeed to obtain 2 of the first records with LAG (as you can check on the 2nd screenshot). Im out of ideas how to proceed from now and need help. I just need the Calculation column take its previous data. I want to automatically calculate it over all the dates. I also tried to make a LAG for the calculation but manually and the result was +1 row more data instead of NULL. This is a headache.
LAG(Data ingested, 1) OVER ( ORDER BY DATE ASC ) AS LAG
You seem to want cumulative sums:
select t.*,
(sum(reconciliation + aves - microa) over (order by date) -
first_value(aves - microa) over (order by date)
) as calculation
from CalcTable t;
Here is a SQL Fiddle.
EDIT:
Based on your comment, you just need to define a group:
select t.*,
(sum(reconciliation + aves - microa) over (partition by grp order by date) -
first_value(aves - microa) over (partition by grp order by date)
) as calculation
from (select t.*,
count(nullif(reconciliation, 0)) over (order by date) as grp
from CalcTable t
) t
order by date;
Imo this could be solved using a "gaps and islands" approach. When Reconciliation>0 then create a gap. SUM(GAP) OVER converts the gaps into island groupings. In the outer query the 'sum_over' column (which corresponds to the 'Calculation') is a cumumlative sum partitioned by the island groupings.
with
gap_cte as (
select *, case when [Reconciliation]>0 then 1 else 0 end gap
from CalcTable),
grp_cte as (
select *, sum(gap) over (order by [Date]) grp
from gap_cte)
select *, sum([Reconciliation]+
(case when gap=1 then 0 else Aves end)-
(case when gap=1 then 0 else Microa end))
over (partition by grp order by [Date]) sum_over
from grp_cte;
[EDIT]
The CASE statement could be CROSS APPLY'ed instead
with
grp_cte as (
select c.*, v.gap, sum(v.gap) over (order by [Date]) grp
from #CalcTable c
cross apply (values (case when [Reconciliation]>0 then 1 else 0 end)) v(gap))
select *, sum([Reconciliation]+
(case when gap=1 then 0 else Aves end)-
(case when gap=1 then 0 else Microa end))
over (partition by grp order by [Date]) sum_over
from grp_cte;
Here is a fiddle
I have a set of data containing some fields: month, customer_id, row_num (RANK), and verified_date.
The rank field indicates the first (1) and second (2) purchase of each customer. I would like to know the time difference between first and second purchase for each customer and show only its first month = month where row_num = 1.
https://i.ibb.co/PjJk5Y0/Capture.png
So my expected result is like below image:
https://i.ibb.co/y5Mww7k/Capture-2.png
I'm using StandardSQL in Google Bigquery.
row_num, verified_date
from table
GROUP BY 1, 2```
We can try using a pivot query here, aggregating by the customer_id:
SELECT
MAX(CASE WHEN row_num = 1 THEN month END) AS month,
customer_id,
1 AS row_num,
DATE_DIFF(MAX(CASE WHEN row_num = 2 THEN verified_date END),
MAX(CASE WHEN row_num = 1 THEN verified_date END), DAY) AS difference
FROM yourTable
GROUP BY
customer_id;
I use SqlExpress
Following is the query using which I get the attached result.
SELECT ReceiptId, Date, Amount, Fine, [Transaction]
FROM (
SELECT ReceiptId, Date, Amount, 'DR' AS [Transaction]
FROM ReceiptCRDR
WHERE (Amount > 0)
UNION ALL
SELECT ReceiptId, Date, Amount, 'CR' AS [Transaction]
FROM ReceiptCR
WHERE (Amount > 0)
UNION ALL
SELECT strInvoiceNo AS ReceiptId, CONVERT(datetime, dtInvoiceDt, 103) AS Date, floatTotal AS Amount, 'DR' AS [Transaction]
FROM tblSellDetails
) AS t
ORDER BY Date
Result
want a new column which would show balance amount.
For example. 1 Row should show -2500, 2nd should -3900, 3rd should -700 and so on.
basically, it requires previous row' Account column's data and carry out calculation based on transaction type.
Sample Result
Well, that looks like SQL-Server , if you are using 2012+ , then use SUM() OVER() :
SELECT t.*,
SUM(CASE WHEN t.transactionType = 'DR'
THEN t.amount*-1
ELSE t.amount END)
OVER(PARTITION BY t.date ORDER BY t.receiptId,t.TransactionType DESC) as Cumulative_Col
FROM (YourQuery Here) t
This will SUM the value when its CR and the value*-1 when its DR
Right now I grouped by date, meaning each day will recalculate this column, if you want it for all time, replace the OVER() with this:
OVER(ORDER BY t.date,t.receiptId,t.TransactionType DESC) as Cumulative_Col
Also, I didn't understand why in the same date, for the same ReceiptId DR is calculated before CR , I've add it to the order by but if thats not what you want then explain the logic better.