A question on using Top. For example, we have this SQL statement:
SELECT TOP (5) WITH TIES orderid, orderdate, custid, empid
FROM Sales.Orders
ORDER BY orderdate DESC;
It orders return rows by orderdate first then select the top most five rows.
But isn't that ORDER clause happens after SELECT clause, which means that the first five order in random will be returned first then those five rows are ordered by orderdate?
The order of commands in the statement doesn't reflect the actual order of operations that SQL follows. See this article which shows the order to be:
from
where
group by
having
select
order by
limit
As you can see, the TOP operation (limit) is the last to be executed.
Question has already an accepted answer. But I would like to quote content from Microsoft Documentation.
Logical Processing Order of the SELECT statement
FROM
ON
JOIN
WHERE
GROUP BY
WITH CUBE or WITH ROLLUP
HAVING
SELECT
DISTINCT
ORDER BY
TOP
But isn't that ORDER clause happens after SELECT clause, which means
that the first five order in random will be returned first then those
five rows are ordered by orderdate ?
No. ORDER BY is processed after the SELECT, but limiting the result set to 5 rows happens even later.
The physical details of actual query processing may vary, but the end result would be as if the server sorted the whole table by orderdate, then picked the top 5 (or more if needed due to ties) rows, return those rows and discard the rest.
I'm trying to find out the most dosed patients in a database. The sum of the doses has to be calculated and then I have to dynamically list out the patients who have been dosed that much. The query has to be dynamic, and there can be more than 5 patients listed - For example, the 5 most doses are 7,6,5,4,3 doses, but 3 people have gotten 5 doses, so I'd have to list out 7 people in total (the patients getting 7,6,5,5,5,4,3 doses). I'm having issues because you cannot refer to a named column in a where clause and I have no idea how to fix this.
The query goes like this:
SELECT
info.NAME, SUM(therapy.DOSE) AS total
FROM
dbo.PATIENT_INFORMATION_TBL info
JOIN
dbo.PATIENT_THERAPY_TBL therapy ON info.HOSPITAL_NUMBER = therapy.HOSPITAL_NUMBER
LEFT JOIN
dbo.FORMULARY_CLINICAL clinical ON clinical.ITEMID = therapy.ITEMID
WHERE
total IN (SELECT DISTINCT TOP 5 SUM(t.DOSE) AS 'DOSES'
FROM dbo.PATIENT_INFORMATION_TBL i
JOIN dbo.PATIENT_THERAPY_TBL t ON i.HOSPITAL_NUMBER = t.HOSPITAL_NUMBER
LEFT JOIN dbo.FORMULARY_CLINICAL c ON c.ITEMID = t.ITEMID
GROUP BY NAME
ORDER BY 'DOSES' DESC)
GROUP BY
info.NAME
ORDER BY
total DESC
The database looks like this:
The main question is: how can I use a where/having clause where I need to compare a calculated column to a list of dynamically calculated values?
I'm using Microsoft's SQL Server 2012. The DISTINCT in the subquery is needed so that only the top 5 dosages appear (e.g. without DISTINCT I get 7,6,5,4,3 with DISTINCT I get 7,6,6,5,4 and my goal is the first one).
Most DBMSes support Standard SQL Analytical Functions like DENSE_RANK:
with cte as
(
SELECT info.NAME, SUM(therapy.DOSE) as total,
DENSE_RANK() OVER (ORDER BY SUM(therapy.DOSE) DESC) AS dr
FROM dbo.PATIENT_INFORMATION_TBL info
JOIN dbo.PATIENT_THERAPY_TBL therapy ON info.HOSPITAL_NUMBER=therapy.HOSPITAL_NUMBER
LEFT JOIN dbo.FORMULARY_CLINICAL clinical ON clinical.ITEMID=therapy.ITEMID
GROUP BY info.NAME
)
select *
from cte
where dr <= 5 -- only the five highest doses
ORDER BY total desc
Btw, you probably don't need the LEFT JOIN as you're not selecting any column from dbo.FORMULARY_CLINICAL
SELECT top 3 a.[CustID],a.[CustName],a.[ContactNo],a.[Address],[EmailID] ,
(select count(1) FROM tblCustomer x) as [RecordCount]
FROM tblCustomer a
where a.[CustID] NOT IN (
SELECT TOP 6 m.[CustID]
FROM tblCustomer m
Order by m.[CreatedOn] desc)
order by a.[CreatedOn] desc
I m trying to Get top 3 Result from above Query but I m getting a lot more than that:
Can someone Recorrect above query ..
TOP in Ms Access includes not just the required number, but all matched results. In this case you have chosen date, so if there are several matched dates, they will all be returned. If you need just three records, order by a unique field in addition to the required sort order. For example
... order by a.[CreatedOn] desc, custid
In below query, I am using GROUP BY clause to get list of recently updated records depends on updated date. But I would like to have the query without a GROUP BY clause because of some internal reasons. Can please any one help me to solve this.
SELECT Proj_UpdatedDate,
Proj_UpdatedBy
FROM ProjectProgress PP
WHERE Proj_UpdatedDate IN (SELECT MAX(Proj_UpdatedDate)
FROM ProjectProgress
GROUP BY
Proj_ProjectID)
ORDER BY
Proj_ProjectID
Using TOP 1 should give you the same result assuming you meant the MAX(Proj_UpdatedDate):
SELECT Proj_UpdatedDate,
Proj_UpdatedBy
FROM ProjectProgress PP
WHERE Proj_UpdatedDate IN (SELECT TOP 1 Proj_UpdatedDate
FROM ProjectProgress
ORDER BY Proj_UpdatedDate DESC)
ORDER BY
Proj_ProjectID
However your query actually returns multiple dates since it's GROUPED BY Proj_ProjectId (the max date for each project). Is that your desired outcome - to show a list of dates that the projects were updated and by whom?
If so, try using ROW_NUMBER():
SELECT Proj_UpdatedDate, Proj_UpdatedBy
FROM (
SELECT ROW_NUMBER() OVER (PARTITION BY Proj_ProjectID ORDER BY Proj_UpdatedBy DESC) rn,
Proj_UpdatedDate,
Proj_UpdatedBy
FROM ProjectProgress
) t
WHERE rn = 1
And here is the SQL Fiddle. This assumes you are running SQL Server 2005 or greater.
Good luck.
I'm working with SQL Server 2005.
My query is:
SELECT (
SELECT COUNT(1) FROM Seanslar WHERE MONTH(tarihi) = 4
GROUP BY refKlinik_id
ORDER BY refKlinik_id
) as dorduncuay
And the error:
The ORDER BY clause is invalid in views, inline functions, derived
tables, subqueries, and common table expressions, unless TOP or FOR
XML is also specified.
How can I use ORDER BY in a sub query?
This is the error you get (emphasis mine):
The ORDER BY clause is invalid in
views, inline functions, derived
tables, subqueries, and common table
expressions, unless TOP or FOR XML is
also specified.
So, how can you avoid the error? By specifying TOP, would be one possibility, I guess.
SELECT (
SELECT TOP 100 PERCENT
COUNT(1) FROM Seanslar WHERE MONTH(tarihi) = 4
GROUP BY refKlinik_id
ORDER BY refKlinik_id
) as dorduncuay
If you're working with SQL Server 2012 or later, this is now easy to fix. Add an offset 0 rows:
SELECT (
SELECT
COUNT(1) FROM Seanslar WHERE MONTH(tarihi) = 4
GROUP BY refKlinik_id
ORDER BY refKlinik_id OFFSET 0 ROWS
) as dorduncuay
Besides the fact that order by doesn't seem to make sense in your query....
To use order by in a sub select you will need to use TOP 2147483647.
SELECT (
SELECT TOP 2147483647
COUNT(1) FROM Seanslar WHERE MONTH(tarihi) = 4
GROUP BY refKlinik_id
ORDER BY refKlinik_id
) as dorduncuay
My understanding is that "TOP 100 PERCENT" doesn't gurantee ordering anymore starting with SQL 2005:
In SQL Server 2005, the ORDER BY
clause in a view definition is used
only to determine the rows that are
returned by the TOP clause. The ORDER
BY clause does not guarantee ordered
results when the view is queried,
unless ORDER BY is also specified in
the query itself.
See SQL Server 2005 breaking changes
Hope this helps,
Patrick
If building a temp table, move the ORDER BY clause from inside the temp table code block to the outside.
Not allowed:
SELECT * FROM (
SELECT A FROM Y
ORDER BY Y.A
) X;
Allowed:
SELECT * FROM (
SELECT A FROM Y
) X
ORDER BY X.A;
You don't need order by in your sub query. Move it out into the main query, and include the column you want to order by in the subquery.
however, your query is just returning a count, so I don't see the point of the order by.
A subquery (nested view) as you have it returns a dataset that you can then order in your calling query. Ordering the subquery itself will make no (reliable) difference to the order of the results in your calling query.
As for your SQL itself:
a) I seen no reason for an order by as you are returning a single value.
b) I see no reason for the sub query anyway as you are only returning a single value.
I'm guessing there is a lot more information here that you might want to tell us in order to fix the problem you have.
Add the Top command to your sub query...
SELECT
(
SELECT TOP 100 PERCENT
COUNT(1)
FROM
Seanslar
WHERE
MONTH(tarihi) = 4
GROUP BY
refKlinik_id
ORDER BY
refKlinik_id
) as dorduncuay
:)
maybe this trick will help somebody
SELECT
[id],
[code],
[created_at]
FROM
( SELECT
[id],
[code],
[created_at],
(ROW_NUMBER() OVER (
ORDER BY
created_at DESC)) AS Row
FROM
[Code_tbl]
WHERE
[created_at] BETWEEN '2009-11-17 00:00:01' AND '2010-11-17 23:59:59'
) Rows
WHERE
Row BETWEEN 10 AND 20;
here inner subquery ordered by field created_at (could be any from your table)
In this example ordering adds no information - the COUNT of a set is the same whatever order it is in!
If you were selecting something that did depend on order, you would need to do one of the things the error message tells you - use TOP or FOR XML
Try moving the order by clause outside sub select and add the order by field in sub select
SELECT * FROM
(SELECT COUNT(1) ,refKlinik_id FROM Seanslar WHERE MONTH(tarihi) = 4 GROUP BY refKlinik_id)
as dorduncuay
ORDER BY refKlinik_id
For me this solution works fine as well:
SELECT tbl.a, tbl.b
FROM (SELECT TOP (select count(1) FROM yourtable) a,b FROM yourtable order by a) tbl
Good day
for some guys the order by in the sub-query is questionable.
the order by in sub-query is a must to use if you need to delete some records based on some sorting.
like
delete from someTable Where ID in (select top(1) from sometable where condition order by insertionstamp desc)
so that you can delete the last insertion form table.
there are three way to do this deletion actually.
however, the order by in the sub-query can be used in many cases.
for the deletion methods that uses order by in sub-query review below link
http://web.archive.org/web/20100212155407/http://blogs.msdn.com/sqlcat/archive/2009/05/21/fast-ordered-delete.aspx
i hope it helps. thanks you all
For a simple count like the OP is showing, the Order by isn't strictly needed. If they are using the result of the subquery, it may be. I am working on a similiar issue and got the same error in the following query:
-- I want the rows from the cost table with an updateddate equal to the max updateddate:
SELECT * FROM #Costs Cost
INNER JOIN
(
SELECT Entityname, costtype, MAX(updatedtime) MaxUpdatedTime
FROM #HoldCosts cost
GROUP BY Entityname, costtype
ORDER BY Entityname, costtype -- *** This causes an error***
) CostsMax
ON Costs.Entityname = CostsMax.entityname
AND Costs.Costtype = CostsMax.Costtype
AND Costs.UpdatedTime = CostsMax.MaxUpdatedtime
ORDER BY Costs.Entityname, Costs.costtype
-- *** To accomplish this, there are a few options:
-- Add an extraneous TOP clause, This seems like a bit of a hack:
SELECT * FROM #Costs Cost
INNER JOIN
(
SELECT TOP 99.999999 PERCENT Entityname, costtype, MAX(updatedtime) MaxUpdatedTime
FROM #HoldCosts cost
GROUP BY Entityname, costtype
ORDER BY Entityname, costtype
) CostsMax
ON Costs.Entityname = CostsMax.entityname
AND Costs.Costtype = CostsMax.Costtype
AND Costs.UpdatedTime = CostsMax.MaxUpdatedtime
ORDER BY Costs.Entityname, Costs.costtype
-- **** Create a temp table to order the maxCost
SELECT Entityname, costtype, MAX(updatedtime) MaxUpdatedTime
INTO #MaxCost
FROM #HoldCosts cost
GROUP BY Entityname, costtype
ORDER BY Entityname, costtype
SELECT * FROM #Costs Cost
INNER JOIN #MaxCost CostsMax
ON Costs.Entityname = CostsMax.entityname
AND Costs.Costtype = CostsMax.Costtype
AND Costs.UpdatedTime = CostsMax.MaxUpdatedtime
ORDER BY Costs.Entityname, costs.costtype
Other possible workarounds could be CTE's or table variables. But each situation requires you to determine what works best for you. I tend to look first towards a temp table. To me, it is clear and straightforward. YMMV.
On possible needs to order a subquery is when you have a UNION :
You generate a call book of all teachers and students.
SELECT name, phone FROM teachers
UNION
SELECT name, phone FROM students
You want to display it with all teachers first, followed by all students, both ordered by. So you cant apply a global order by.
One solution is to include a key to force a first order by, and then order the names :
SELECT name, phone, 1 AS orderkey FROM teachers
UNION
SELECT name, phone, 2 AS orderkey FROM students
ORDER BY orderkey, name
I think its way more clear than fake offsetting subquery result.
I Use This Code To Get Top Second Salary
I am Also Get Error Like
The ORDER BY clause is invalid in views, inline functions, derived tables, subqueries, and common table expressions, unless TOP or FOR XML is also specified.
TOP 100 I Used To Avoid The Error
select * from (
select tbl.Coloumn1 ,CONVERT(varchar, ROW_NUMBER() OVER (ORDER BY (SELECT 1))) AS Rowno from (
select top 100 * from Table1
order by Coloumn1 desc) as tbl) as tbl where tbl.Rowno=2