I have an activity log table on a site. There are columns for date/time, userID and IP address for each log-in.
I want to retrieve a list of unique usernames and the most recent IP address they logged in from.
What's the best way to retrieve this from the table using t-sql on SQL Server?
A portable approach is:
select l.userID, l.Date, l.IpAddress
from (
select userID, max(Date) as MaxDate
from Log
group by userID
) lm
inner join Log l on lm.userID = l.userID
and lm.MaxDate = l.Date
If you have SQL Server 2005+, you can also do:
select * from
(
select userID, Date, IpAddress,
Rank() over (Partition BY userID order by Date DESC) as Rank
from Log
) tmp
where Rank = 1
I'm guessing at some column / table names here, and I'm assuming username comes from a table (and you aren't storing the username in the log each time):
;WITH x AS
(
SELECT userID, IPaddress, rn = ROW_NUMBER() OVER
(PARTITION BY UserID ORDER BY datetimecolumn DESC)
FROM dbo.LogTable
)
SELECT u.username, x.IPAddress
FROM x INNER JOIN dbo.Users AS u
ON u.userID = x.userID
WHERE x.rn = 1;
select distinct(user_name), (select top 1 IP_address from log_table where user_name=LOG.user_name order by log_date desc)
from log_table LOG
Related
I have following result set,
Now with above results i want to print the records via select query as below attached image
Please note, I will have only two types of columns in output Present Employee & Absent Employees.
I tried using pivot tables, temporary table but cant achieve what I want.
One method would be to ROW_NUMBER each the the "statuses" and then use a FULL OUTER JOIN to get the 2 datasets into the appropriate columns. I use a FULL OUTER JOIN as I assume you could have a different amount of employees who were present/absent.
CREATE TABLE dbo.YourTable (Name varchar(10), --Using a name that doesn't require delimit identification
Status varchar(7), --Using a name that doesn't require delimit identification
Days int);
GO
INSERT INTO dbo.YourTable(Name, Status, Days)
VALUES('Mal','Present',30),
('Jess','Present',20),
('Rick','Absent',30),
('Jerry','Absent',10);
GO
WITH RNs AS(
SELECT Name,
Status,
Days,
ROW_NUMBER() OVER (PARTITION BY Status ORDER BY Days DESC) AS RN
FROM dbo.YourTable)
SELECT P.Name AS PresentName,
P.Days AS PresentDays,
A.Name AS AbsentName,
A.Days AS AbsentDays
FROM (SELECT R.Name,
R.Days,
R.Status,
R.RN
FROM RNs R
WHERE R.Status = 'Present') P
FULL OUTER JOIN (SELECT R.Name,
R.Days,
R.Status,
R.RN
FROM RNs R
WHERE R.Status = 'Absent') A ON P.RN = A.RN;
GO
DROP TABLE dbo.YourTable;
db<>fiddle
2 CTE's is actually far neater:
WITH Absents AS(
SELECT Name,
Status,
Days,
ROW_NUMBER() OVER (ORDER BY Days DESC) AS RN
FROM dbo.YourTable
WHERE Status = 'Absent'),
Presents AS(
SELECT Name,
Status,
Days,
ROW_NUMBER() OVER (ORDER BY Days DESC) AS RN
FROM dbo.YourTable
WHERE Status = 'Present')
SELECT P.Name AS PresentName,
P.Days AS PresentDays,
A.Name AS AbsentName,
A.Days AS AbsentDays
FROM Absents A
FULL OUTER JOIN Presents P ON A.RN = P.RN;
I have a table that logs all updates made to an application. I want to query the table and return the last update by [Timestamp] and the update before that for a different value [ITEM]. I'm struggling to figure out how to get what i need. I'm returning more than one record for each ID and don't want that.
;WITH cte AS
(
SELECT
ID,
LAG(ITEM) OVER (PARTITION BY ID ORDER BY timestamp DESC) AS ITEM,
ROW_NUMBER() OVER (PARTITION BY ID ORDER BY timestamp DESC) RN
FROM
MyLoggingTable
WHERE
accountid = 1234
)
SELECT
cte.ID,
dl.ITEM,
DL.timestamp
FROM
cte
JOIN
MyLoggingTable DL ON cte.ID = DL.ID
WHERE
rn = 1
AND cte.ID IN ('id here | Sub select :( ..')
Is ID unique? Because if it is, your code shouldn't return duplicates. If it isn't, you will get duplicates because you are joining back to the MyLoggingTable which isn't needed. You should just move those columns (dl.Item & dl.timestamp) into the cte and return them from the cte like you did cte.ID.
I removed the LAG since you didn't return that column in your final query.
;WITH cte AS
(
SELECT
ID,
ITEM,
[timestamp],
--LAG(ITEM) OVER (PARTITION BY ID ORDER BY timestamp DESC) AS ITEM,
ROW_NUMBER() OVER (PARTITION BY ID ORDER BY timestamp DESC) RN
FROM
MyLoggingTable
WHERE
accountid = 1234
)
SELECT
cte.ID,
cte.ITEM,
cte.timestamp
FROM
cte
WHERE
rn = 1
AND cte.ID IN ('id here | Sub select :( ..')
Note, if you wanted the second to the last item, as you stated in your comments, make rn=2
I have 36 Sales tables each referred to one store:
st1.dbo.Sales
st2.dbo.Sales
...
st35.dbo.Sales
st36.dbo.Sales
Each record has the following key columns:
UserName, PostalCode, Location, Country, InvoiceAmount, ItemsCount, StoreID
Here is SQLFiddle
I need to copy into Customers table all Username (and their details) that are not already present into Customers
in case of duplicated it is required to use the fields of record where InvoiceAmount is MAX
I tried to build a query but looks too complicated and it is also wrong because in CROSS APPLY should consider the full list of Sales Tables
INSERT INTO Customers (.....)
SELECT distinct
d.UserName,
w.postalCode,
w.location,
W.country,
max(w.invoiceamount) invoiceamount,
max(w.itemscount) itemscount,
w.storeID
FROM
(SELECT * FROM st1.dbo.Sales
UNION
SELECT * FROM st2.dbo.Sales
UNION
...
SELECT * FROM st36.dbo.Sales) d
LEFT JOIN
G.dbo.Customers s ON d.Username = s.UserName
CROSS APPLY
(SELECT TOP (1) *
FROM s.dbo.[Sales]
WHERE d.Username=w.Username
ORDER BY InvoiceAmount DESC) w
WHERE
s.UserName IS NULL
AND d.username IS NOT NULL
GROUP BY
d.UserName, w.postalCode, w.location,
w.country, w.storeID
Can somebody please give some hints?
As a basic SQL query, I'd create a row_number in the inner subquery and then join to customers and then isolated the max invoice number for each customer not in the customer table.
INSERT INTO Customers (.....)
SELECT w.UserName,
w.postalCode,
w.location,
w.country,
w.invoiceamount,
w.itemscount,
w.storeID
FROM (select d.*,
row_number() over(partition by d.Username order by d.invoiceamount desc) rownumber
from (SELECT *
FROM st1.dbo.Sales
UNION
SELECT *
FROM st2.dbo.Sales
UNION
...
SELECT *
FROM st36.dbo.Sales
) d
LEFT JOIN G.dbo.Customers s
ON d.Username = s.UserName
WHERE s.UserName IS NULL
AND d.username IS NOT NULL
) w
where w.rownumber = 1
Using your fiddle this will select distinct usernames rows with max invoiceamount
with d as(
SELECT * FROM Sales
UNION
SELECT * FROM Sales2
)
select *
from ( select *,
rn = row_number() over(partition by Username order by invoiceamount desc)
from d) dd
where rn=1;
step 1 - use cte .
select username , invoiceamount ,itemscount from Sales
UNION all
select user name , invoiceamount ,itemscount from Sales
.....
...
step 2
next cte use group by and get max invoiceamount ,itemscount for user of last result set.
,cte2 as (
select user name , max (invoiceamount) as invoiceamount ,max(itemscount) as itemscount from cte)
step3
use left join with user table and find missing record and itemscount invoiceamount
i have many duplicate job id but entry date is can not be duplicate. i need to fetch always unique job id based on last entry date. i have solved it with the below query but like to know is there any better way to form the same sql when data would be huge for best performance. please guide me thanks.
SELECT A.JID,A.EntryDate,RefundDate,Comments,Refund, ActionBy
FROM (
(
select JID, Max(EntryDate) AS EntryDate
from refundrequested
GROUP BY JID
) A
Inner JOIN
(
SELECT JID,ENTRYDATE,refundDate,Comments,refund,ActionBy
from refundrequested
) B
ON A.JID=B.JID AND A.EntryDate = B.EntryDate
)
Using the row_number() function is usually a bit faster:
select *
from (
select row_number() over (partition by jid
order by EntryDate desc) as rn
, *
from refundrequested
) as SubQueryAlias
where rn = 1
Query:
SELECT t1.JID,
t1.EntryDate,
t1.RefundDate,
t1.Comments,
t1.Refund,
t1.ActionBy
FROM refundrequested t1
LEFT JOIN refundrequested t2
ON t2.JID = t1.JID
AND t2.EntryDate > t1.EntryDate
WHERE t2.JID is null
I have a table :
EventLog (
EventID (INT),
UserID (VARCHAR(50),
Event (NTEXT),
EventDate(DateTime),
DocuvmentID(INT)
)
I need to write a query to get the latest event, datetime for a bunch of userId which will be
WHERE UserID IN ( 'john','tom'...etc)
How can I do that?
SELECT y.UserID, y.Event, y.EventDate
FROM (SELECT UserId, MAX(EventDate) AS MaxDate
FROM YourTable
WHERE UserId IN ('john','tom',...)
GROUP BY UserId) t
INNER JOIN YourTable y
ON t.UserId = y.UserId
AND t.MaxDate = y.EventDate
With a simple CTE:
;WITH LatestDates AS
(SELECT
EventID, UserID,
Event, EventDate,
DocumentID,
ROW_NUMBER() OVER(PARTITION BY UserID ORDER BY EventDate DESC) AS 'RowNum'
)
SELECT *
FROM LatestDates
WHERE RowNum = 1 AND UserID IN (........)
This partitions your data by some criteria (I picked UserID as an option - might be something else for you), then numbers each group sequentially starting at 1, ordered by another criteria (here: EventDate DESC) - so the most recent event for each "partition" has RowNum = 1 which is what I select from that CTE
select
UserID,
MAX(EventDate) AS LatestEventDate
from
EventLog
where
UserID in ('john','tom')
group by
UserID