SQL Server : get row order number in given month - sql

Question

I am using SQL Server and trying to get the order of transaction in a month, for example if I have 10 transactions in a month I want to know when the selected transaction occurred, if it was the 1st, 2nd, 3rd etc. transaction in that month. I tried using ROW_NUMBER() like
SELECT
transactionid,
ROW_NUMBER() OVER(ORDER BY transactionexecutiontime ASC) rowOrderNumber
FROM
dbo.exportebop
WHERE
MONTH(transactionexecutiontime) = 1
ORDER BY
transactionexecutiontime ASC
This works if I do not specify the TransactionID because I get multiple rows, the moment I use TransactionID = idNumber It returns a single row and row_number() is always 1
I know ROW_NUMBER() counts the result set but I need a way to calculate when order number in a month using the TransactionExecutionTime instead.
Does anyone know how I can achieve this?

Answer 1

I think you need to apply Row_Number first then after that you can apply filtering. I will use CTE to do that -
;WITH CTE AS (
SELECT
TransactionID,
ROW_NUMBER() OVER(ORDER BY TransactionExecutionTime ASC) rowOrderNumber
FROM dbo.EXPORTEBOP
WHERE MONTH(TransactionExecutionTime) = 1
)
SELECT *
FROM CTE
WHERE TransactionID = 1
ORDER BY rowOrderNumber ASC
As a sub-query-
DECLARE #Month INT = 1
SELECT *
FROM (
SELECT
TransactionID,
ROW_NUMBER() OVER(ORDER BY TransactionExecutionTime ASC) rowOrderNumber
FROM dbo.EXPORTEBOP
WHERE MONTH(TransactionExecutionTime) = #Month
) X
WHERE TransactionID = 1
ORDER BY rowOrderNumber ASC

Answer 2

If you want all months listed, you can partition the row number by month:
SELECT
transactionid,
Month = MONTH(transactionexecutiontime),
rowOrderNumber = ROW_NUMBER() OVER(
PARTITION BY
MONTH(transactionexecutiontime) -- Will start different "row numbers" for each month
ORDER BY
transactionexecutiontime ASC)
FROM
dbo.exportebop
ORDER BY
MONTH(transactionexecutiontime),
transactionexecutiontime ASC
If you want a particular transaction ID, you can't filter it on the same result set as the ROW_NUMBER() because it will only generate a row number for that result set, which will only contain 1 row (your filtered transaction). You will have to filter it on a another query that references the first (with a CTE or a subquery):
;WITH RankedTransactionsByMonth AS
(
SELECT
transactionid,
Month = MONTH(transactionexecutiontime),
rowOrderNumber = ROW_NUMBER() OVER(
PARTITION BY
MONTH(transactionexecutiontime) -- Will start different "row numbers" for each month
ORDER BY
transactionexecutiontime ASC)
FROM
dbo.exportebop
-- No Order by in subqueries without TOP!!
)
SELECT
R.*
FROM
RankedTransactionsByMonth AS R
WHERE
R.transactionid = 1