How do i get the latest user udpated column value in a table based on timestamp entry on a different table in SQL Server? - sql

Question

I have a temp table #StatusInfo with the following data
+---------+--------------+-------+-------------------------+--+
| OrderNo | GroupLineNum | Type1 | UpdateDate | |
+---------+--------------+-------+-------------------------+--+
| Order85 | NULL | 1 | 2019-11-25 05:15:55.000 | |
+---------+--------------+-------+-------------------------+--+
| Order86 | NULL | 1 | 2019-11-25 05:15:55.000 | |
+---------+--------------+-------+-------------------------+--+
| Order86 | 2 | 2 | 2019-11-25 05:32:23.773 | |
+---------+--------------+-------+-------------------------+--+
| Order87 | NULL | 1 | 2019-11-25 05:15:55.000 | |
+---------+--------------+-------+-------------------------+--+
| Order87 | 1 | 2 | 2019-11-25 05:43:37.637 | | B
+---------+--------------+-------+-------------------------+--+
| Order87 | 2 | 2 | 2019-11-25 05:42:32.390 | | A
+---------+--------------+-------+-------------------------+--+
| Order88 | NULL | 1 | 2019-11-25 06:35:13.000 | |
+---------+--------------+-------+-------------------------+--+
| Order88 | 1 | 2 | 2019-11-25 06:39:16.170 | |
+---------+--------------+-------+-------------------------+--+
Any update the user does on an order will be pulled into this temp table. Type 1 column with value 2 denotes a 'Required Date' field change by the user. The timestamp when the user made the change is the last column.
I have another temp table #LineInfo with the following data. This table is created by joining other tables and a left join with the above table too. The 'LineNum' column from below table will match the 'GroupLineNum' column in the above table for Type1=2
+---------+-----------+---------+------------+-------------------------+-------+
| OrderNo | RowNumber | LineNum | TotalCost | ReqDate | Type1 |
+---------+-----------+---------+------------+-------------------------+-------+
| Order85 | 1 | 1 | 309.110000 | 2019-10-30 23:59:00.000 | 1 |
+---------+-----------+---------+------------+-------------------------+-------+
| Order85 | 2 | 2 | 265.560000 | 2019-10-30 23:59:00.000 | 1 |
+---------+-----------+---------+------------+-------------------------+-------+
| Order86 | 1 | 1 | 309.110000 | 2019-10-30 23:59:00.000 | 1 |
+---------+-----------+---------+------------+-------------------------+-------+
| Order86 | 2 | 2 | 265.560000 | 2019-12-28 23:59:00.000 | 2 |
+---------+-----------+---------+------------+-------------------------+-------+
| Order87 | 1 | 1 | 309.110000 | 2020-01-31 23:59:00.000 | 2 |
+---------+-----------+---------+------------+-------------------------+-------+
| Order87 | 2 | 2 | 265.560000 | 2020-01-01 23:59:00.000 | 2 |
+---------+-----------+---------+------------+-------------------------+-------+
| Order88 | 1 | 1 | 309.110000 | 2019-11-29 23:59:00.000 | 2 |
+---------+-----------+---------+------------+-------------------------+-------+
| Order88 | 2 | 2 | 265.560000 | 2019-12-31 23:59:00.000 | 2 |
+---------+-----------+---------+------------+-------------------------+-------+
I will be joining #lineInfo with other tables to generate a new table with only one record for an orderno. Its grouped by orderno.
What I need to do is ensure that the new selectquery will have a column 'ReqDate' which will be the latest ReqDate value for the order.
For example, Order87 has two lines in the order. User updated Line 2 first at '2019-11-25 05:42:32.390' as seen in the row marked 'A' followed by Line 1 marked B # '2019-11-25 05:43:37.637 ' from the first table.
The new query should have the data from LineInfo and only the 'ReqDate' value matching the 'LineNum' that has the maximum of 'UpdateDate' column for Type1=2 and group by orderno.
So in our example, the output should have the ReqDate value '2020-01-31 23:59:00.000'.
In short, an order should have the most recently updated required date. Order can have multiple line items where reqdate is udpated. If there is no entry in #StatusInfo table with Type2 for an order, then any one of the ReqDate value from the #LineInfo table will suffice. Maybe the first line
I wrote something like this but it doesnt pull orders without any entry in StatusInfo table. Those orders will have a default value even though user didnt udpate and i am not sure how to join the result of this with LineInfo table to set the latest value
Select SIT.Orderno, max_date,grouplinenum
from #StatusInfo SIT
inner join
(SELECT Orderno, MAX(ActDate) as max_date
FROM #StatusInfo SI
WHERE SI.Type1=2
GROUP BY SI.Orderno)a
on a.Orderno = SIT.Orderno and a.max_date = SIT.ActDate

Answer 1

This is what I did. I created the blow CTE to load orders with req date change in order of Updated date and assigned it row number. Record with row number 1 will be the most recently updated date
;WITH cteLatestReqDate AS ( --We need to pull the latest ReqDate value the user set. So we are are ordering the SIT table by ActDate and assigning a row number and respective line's required date here
SELECT SIT.OrderNo, SIT.UpdateDate, SIT.GroupLineNum, LLI.ReqDate,
ROW_NUMBER() OVER (PARTITION BY SIT.OrderNo ORDER BY ActDate DESC) AS RowNum
FROM #StatusInfo SIT INNER JOIN #LineLevelInfo LLI ON SIT.OrderNo = OI.OrderNo AND SIT.GroupLineNum = LLI.LineNum
WHERE SIT.Type1 = 2
)
and then I added the below condition to my select query. Below select query is partial
SELECT
CASE WHEN MAX(LRD.ReqDate) IS NULL THEN CAST(FORMAT(MAX(LLI.ReqDate), 'yyMMdd') AS NVARCHAR(10))
ELSE CAST(FORMAT(MAX(LRD.ReqDate), 'yyMMdd') AS NVARCHAR(10)) END AS LatestReqDate
FROM #LineLevelInfo LLI
LEFT JOIN(SELECT * FROM cteLatestReqDate WHERE RowNum = 1)LRD ON LRD.OrderNo = LLI.OrderNo And LRD.GroupLineNum = LLI.LineNum