I am trying to sum my column named target where measured_component is equal to a specific condition and add it to my table but am having trouble. Ultimately I want to add 4 new rows for the 4 conditions to my current table with all the columns null except for the time_value which would be the month for each total based on the condition.
I am using the below query.
select sum(TARGET) as TARGET_TOTAL
from REF_targets
where MEASURED_COMPONENT ='dispatch'
or MEASURED_COMPONENT='acknoweledge'
or MEASURED_COMPONENT= 'DRIVE'
or MEASURED_COMPONENT= 'ENROUTE'
group by TIME_VALUE
When I have the conditions grouped, I get a crazy number for my sum, but if I create separate queries I get the correct total.
select time_value
, sum(TARGET) as TARGET_TOTAL
from REF_targets
where MEASURED_COMPONENT ='dispatch'
group by TIME_VALUE
I cant select all with this query because I keep getting an error saying that I need to add ALL the columns to the group by which ultimately gives me a mirror of the data I already have for target just in a new column.
Please help,
Thanks!
You get a large number because you don't put MEASURED_COMPONENT in the GROUP BY. This should give you sum for each MEASURED_COMPONENT.
select TIME_VALUES, MEASURED_COMPONENT, sum(TARGET) as TARGET_TOTAL
from REF_targets
where MEASURED_COMPONENT ='dispatch'
or MEASURED_COMPONENT='acknoweledge'
or MEASURED_COMPONENT= 'DRIVE'
or MEASURED_COMPONENT= 'ENROUTE'
group by TIME_VALUES, MEASURED_COMPONENT
Related
Actually I am building a Skype like tool wherein I have to show last 10 distinct users who have logged in my web application.
I have maintained a table in sql-server where there is one field called last_active_time. So, my requirement is to sort the table by last_active_time and show all the columns of last 10 distinct users.
There is another field called WWID which uniquely identifies a user.
I am able to find the distinct WWID but not able to select the all the columns of those rows.
I am using below query for finding the distinct wwid :
select distinct(wwid) from(select top 100 * from dbo.rvpvisitors where last_active_time!='' order by last_active_time DESC) as newView;
But how do I find those distinct rows. I want to show how much time they are away fromm web apps using the diff between curr time and last active time.
I am new to sql, may be the question is naive, but struggling to get it right.
If you are using proper data types for your columns you won't need a subquery to get that result, the following query should do the trick
SELECT TOP 10
[wwid]
,MAX([last_active_time]) AS [last_active_time]
FROM [dbo].[rvpvisitors]
WHERE
[last_active_time] != ''
GROUP BY
[wwid]
ORDER BY
[last_active_time] DESC
If the column [last_active_time] is of type varchar/nvarchar (which probably is the case since you check for empty strings in the WHERE statement) you might need to use CAST or CONVERT to treat it as an actual date, and be able to use function like MIN/MAX on it.
In general I would suggest you to use proper data types for your column, if you have dates or timestamps data use the "date" or "datetime2" data types
Edit:
The query aggregates the data based on the column [wwid], and for each returns the maximum [last_active_time].
The result is then sorted and filtered.
In order to add more columns "as-is" (without aggregating them) just add them in the SELECT and GROUP BY sections.
If you need more aggregated columns add them in the SELECT with the appropriate aggregation function (MIN/MAX/SUM/etc)
I suggest you have a look at GROUP BY on W3
To know more about the "execution order" of the instruction you can have a look here
You can solve problem like this by rank ordering the results by a key and finding the last x of those items, this removes duplicates while preserving the key order.
;
WITH RankOrdered AS
(
SELECT
*,
wwidRank = ROW_NUMBER() OVER (PARTITION BY wwid ORDER BY last_active_time DESC )
FROM
dbo.rvpvisitors
where
last_active_time!=''
)
SELECT TOP(10) * FROM RankOrdered WHERE wwidRank = 1
If my understanding is right, below query will give the desired output.
You can have conditions according to your need.
select top 10 distinct wwid from dbo.rvpvisitors order by last_active_time desc
Okay it has been quite some time since I have used SQL Server very intensively for writing queries.
There has to be some gotcha that I am missing.
As per my understanding the following two queries should return the same number of duplicate records
SELECT COUNT(INVNO)
, INVNO
FROM INVOICE
GROUP BY INVNO
HAVING COUNT(INVNO) > 1
ORDER BY INVNO
SELECT DISTINCT invno
FROM INVOICE
ORDER BY INVNO
There are no null values in INVNO
Where could I be possible going wrong?
Those queries will not return same results. First one will only give you INVNO values that have duplicates, second will give all unique INVNO values, even if they appear only once in entire table.
the group by query will filter our all the single invoices while the distinct will simply pick one from every invoice. First query is a subset of the second
In addition to what Adam said, the GROUP BY will sort the data on the GROUPed columns.
I am looking to retrieve only the second (duplicate) record from a data set. For example in the following picture:
Inside the UnitID column there is two separate records for 105. I only want the returned data set to return the second 105 record. Additionally, I want this query to return the second record for all duplicates, not just 105.
I have tried everything I can think of, albeit I am not that experience, and I cannot figure it out. Any help would be greatly appreciated.
You need to use GROUP BY for this.
Here's an example: (I can't read your first column name, so I'm calling it JobUnitK
SELECT MAX(JobUnitK), Unit
FROM JobUnits
WHERE DispatchDate = 'oct 4, 2015'
GROUP BY Unit
HAVING COUNT(*) > 1
I'm assuming JobUnitK is your ordering/id field. If it's not, just replace MAX(JobUnitK) with MAX(FieldIOrderWith).
Use RANK function. Rank the rows OVER PARTITION BY UnitId and pick the rows with rank 2 .
For reference -
https://msdn.microsoft.com/en-IN/library/ms176102.aspx
Assuming SQL Server 2005 and up, you can use the Row_Number windowing function:
WITH DupeCalc AS (
SELECT
DupID = Row_Number() OVER (PARTITION BY UnitID, ORDER BY JobUnitKeyID),
*
FROM JobUnits
WHERE DispatchDate = '20151004'
ORDER BY UnitID Desc
)
SELECT *
FROM DupeCalc
WHERE DupID >= 2
;
This is better than a solution that uses Max(JobUnitKeyID) for multiple reasons:
There could be more than one duplicate, in which case using Min(JobUnitKeyID) in conjunction with UnitID to join back on the UnitID where the JobUnitKeyID <> MinJobUnitKeyID` is required.
Except, using Min or Max requires you to join back to the same data (which will be inherently slower).
If the ordering key you use turns out to be non-unique, you won't be able to pull the right number of rows with either one.
If the ordering key consists of multiple columns, the query using Min or Max explodes in complexity.
I'm new to T-SQL and this question is T-SQL Count 101.
I'm studying T-SQL with this site http://sqlmag.com/t-sql/t-sql-101-lesson-4 but I can't figure out Which part of coding says WHERE(column_name) to execute 'COUNT' if it makes sense? In other words, how does this COUNT know what to count? It just says COUNT everything as Reviews from MovieReview table.....
SELECT MovieName,
LEFT(REPLICATE('* ',AVG(Stars)),10)
AS 'Stars',
COUNT(*) AS 'Reviews'
FROM MovieReview
GROUP BY MovieName
HAVING COUNT(*) >= 4
ORDER BY Stars
Result:
The TABLE name is MovieReview that contains the ratings that the five employees have given to movies they’ve watched in their spare time. This table contains four columns: EmployeeID, Genre, MovieName, and Stars. The Stars field specifies the movie’s rating, where 1 star is the worst rating and 5 is the best rating.
I understand below coding because it specified WHERE. Count everything as '...' From Employee table Where salary is less than 3000.
SELECT COUNT(*)
AS 'Impoverished'
FROM Employee
WHERE Salary < 30000
I need to learn creating reports from Data Warehouse. I learned SQL but most of sites use T-SQL when creating reports, I don't know why.
Thanks in advance.
count(*) counts the number of rows that match the where clause if a where clause is given, per distinct combination of the group by columns if a group by column is given.
Except for the behavior noted in the previous sentence, count(*) ignores the values in those rows.
I have a query that's supposed to pull all reservations from one table and then sum the Quantity column from a linked table. I've set a right join on the query but for some reason, it's only showing reservations that have at least one quantity record. The query below should return 4 rows, 3 with a sum of zero quantity but is only returning a single row. Any ideas?
SELECT
tblReservations.Subaccount,
SUM(tblBilling_Detail.Quantity)
FROM tblBilling_Detail
RIGHT JOIN tblReservations
ON tblBilling_Detail.Linked_Account = tblReservations.Subaccount
WHERE Usage_Start
BETWEEN tblReservations.Reservation_Start
AND tblReservations.Reservation_End
GROUP BY tblReservations.Subaccount
It was the WHERE clause. All fixed.