In order to build a statistical report, i need to execute this kind of request, for each 5000 agencies, and each 5 state, so 25 000 requests :
select count(*) from transaction where state == 1 and where id_agency==1;
select avg(duration) from transaction where state == 1 and where id_agency==1;
How to build a stored procedure which gathers all the results of these requests, into one list key-value ?
CountAgency1CountState1 = 123;
CountAgency2CountState5 = 645;
CountAgency8AverageState7 = 987;
Data Table structure : 2 tables :
Table Transaction : id_transac, duration, state, idAgency
Table Agency : idAgency, adress, city
It seems like what you need is to group by ID and State
SELECT ID_Agency
,State
,Count(*) [ID_Count]
,AVG(Duration) [Avg_Duration]
FROM Transaction
group by ID_Agency
,State
This will give you one row per ID and State with the 2 values you need.
actually by assuming your data we can proceed by using AVG() and GROUP BY to get count basing on ID .it's example if you provide exact data we can get some more accurate output
CREATE table #T(ID INT,Value INT)
INSERT INTO #T (ID,Value)values (1,10),(1,20),(1,30),(2,10),(2,20),(2,30)
GO
CREATE PROCEDURE Getaverage
(#i_id INT)
AS
BEGIN
select DISTINCT COUNT(ID) ,AVG(value),SUM(VALUE) from #T t
WHERE (t.id = #i_id OR #i_id IS NULL)
GROUP BY ID
END
Why not do it all in the one query?
SELECT 'CountAgency' +
CAST(idAgency as varchar) +
'CountState' +
CAST(state as varchar) As Name
,CountAgency
,AvgDuration
FROM (
SELECT idAgency
,state
,COUNT(*) As CountAgency
,AVG(T.Duration) As AvgDuration
FROM [Transaction]
GROUP BY idAgency, state
) InnerQuery
Related
Is it possible to have the result set of a stored procedure limited to 25 results, but also return the total number of results (not limited)? This stored procedure is used in a search page on a web application, so we have paged results (displaying 25 results per page), but need the ##rowcount to display 'Your results returned ___' results.
I've tried the obvious approaches like
SELECT COUNT(*)
FROM [derived table containing the search query]
but due to data structure, the number of rows in participating tables, the COUNT(*) is taking longer than the query itself.
I apologize in advance for the formatting sticklers out there, still very new to this!
You could try to use WITH common_table_expression.
WITH ResultSet AS
(
select CustomerID,CompanyName, ROW_NUMBER() over (Order by CompanyName asc) as RowNumber from Customers
)
select CustomerID,CompanyName,(Select Max(RowNumber) From ResultSet) AS TotalCount from ResultSet
where RowNumber > 0 and RowNumber < 25
In this case CompanyName would be sorting field and you can calculate the max RowNumber then apply pagination on it.
Another option is
declare #pageIndex int = 1
declare #pageCount int = 25
SELECT CustomerID, CompanyName,COUNT(*) OVER () as TotalCount
FROM Customers
ORDER BY CompanyName
OFFSET ( #pageIndex-1 ) * #pageCount ROWS
FETCH NEXT #pageCount ROWS ONLY
Demo
If you query the Count not from the derived table but from the original tables, and only get only the count that should be faster than from a derived table. You can then store that in an output parameter.
Other then that I don't see another way to do this.
so why not do:
declare #numrows int;
SELECT #numrows = Count(*) FROM sys.databases;
PRINT #numrows; -- or assign to output param
I'm quite new to T-SQL and currently struggling with an insert statement in my stored procedure: I use as a parameter in the stored procedure a list of ids of type INT.
If the list is NOT empty, I want to store the ids into the table Delivery.
To pass the list of ids, i use a table type:
CREATE TYPE tIdList AS TABLE
(
ID INT NULL
);
GO
Maybe you know a better way to pass a list of ids into a stored procedure?
However, my procedure looks as follows:
-- parameter
#DeliveryModelIds tIdList READONLY
...
DECLARE #StoreId INT = 1;
-- Delivery
IF EXISTS (SELECT * FROM #DeliveryModelIds)
INSERT [MyDB].[Delivery] ([DeliveryModelId], [StoreId])
OUTPUT inserted.DeliveryId
SELECT ID FROM #DeliveryModelIds;
If the list has values, I want to store the values into the DB as well as the StoreId which is always 1.
If I insert the DeliveryIds 3,7,5 The result in table Delivery should look like this:
DeliveryId | StoreId | DeliveryModelId
1...............| 1...........| 3
2...............| 1...........| 7
3...............| 1...........| 5
Do you have an idea on how to solve this issue?
THANKS !
You can add #StoreId to your select for your insert.
...
IF EXISTS (SELECT * FROM #DeliveryModelIds)
INSERT [MyDB].[Delivery] ([DeliveryModelId], [StoreId])
OUTPUT inserted.DeliveryId
SELECT ID, #StoreId FROM #DeliveryModelIds;
Additionally, if you only want to insert DeliveryModelId that do not currently exist in the target table, you can use not exists() in the where clause like so:
...
IF EXISTS (SELECT * FROM #DeliveryModelIds)
INSERT [MyDB].[Delivery] ([DeliveryModelId], [StoreId])
OUTPUT inserted.DeliveryId
SELECT dmi.ID, #StoreId
FROM #DeliveryModelIds dmi
where not exists (
select 1
from MyDb.Delivery i
where i.StoreId = #StoreId
and i.DeliveryModeId = dmi.ID
);
You need to modify the INSERT statement to:
INSERT [MyDB].[Delivery] ([DeliveryModelId], [StoreId])
OUTPUT inserted.DeliveryId
SELECT ID, 1 FROM #DeliveryModelIds;
So you are also selecting a literal, 1, along with ID field.
I currently have a stored procedure in MSSQL where I execute a SELECT-statement multiple times based on the variables I give the stored procedure. The stored procedure counts how many results are going to be returned for every filter a user can enable.
The stored procedure isn't the issue, I transformed the select statement from te stored procedure to a regular select statement which looks like:
DECLARE #contentRootId int = 900589
DECLARE #RealtorIdList varchar(2000) = ';880;884;1000;881;885;'
DECLARE #publishSoldOrRentedSinceDate int = 8
DECLARE #isForSale BIT= 1
DECLARE #isForRent BIT= 0
DECLARE #isResidential BIT= 1
--...(another 55 variables)...
--Table to be returned
DECLARE #resultTable TABLE
(
variableName varchar(100),
[value] varchar(200)
)
-- Create table based of inputvariable. Example: turns ';18;118;' to a table containing two ints 18 AND 118
DECLARE #RealtorIdTable table(RealtorId int)
INSERT INTO #RealtorIdTable SELECT * FROM dbo.Split(#RealtorIdList,';') option (maxrecursion 150)
INSERT INTO #resultTable ([value], variableName)
SELECT [Value], VariableName FROM(
Select count(*) as TotalCount,
ISNULL(SUM(CASE WHEN reps.ForRecreation = 1 THEN 1 else 0 end), 0) as ForRecreation,
ISNULL(SUM(CASE WHEN reps.IsQualifiedForSeniors = 1 THEN 1 else 0 end), 0) as IsQualifiedForSeniors,
--...(A whole bunch more SUM(CASE)...
FROM TABLE1 reps
LEFT JOIN temp t on
t.ContentRootID = #contentRootId
AND t.RealEstatePropertyID = reps.ID
WHERE
(EXISTS(select 1 from #RealtorIdTable where RealtorId = reps.RealtorID))
AND (#SelectedGroupIds IS NULL OR EXISTS(select 1 from #SelectedGroupIdtable where GroupId = t.RealEstatePropertyGroupID))
AND (ISNULL(reps.IsForSale,0) = ISNULL(#isForSale,0))
AND (ISNULL(reps.IsForRent, 0) = ISNULL(#isForRent,0))
AND (ISNULL(reps.IsResidential, 0) = ISNULL(#isResidential,0))
AND (ISNULL(reps.IsCommercial, 0) = ISNULL(#isCommercial,0))
AND (ISNULL(reps.IsInvestment, 0) = ISNULL(#isInvestment,0))
AND (ISNULL(reps.IsAgricultural, 0) = ISNULL(#isAgricultural,0))
--...(Around 50 more of these WHERE-statements)...
) as tbl
UNPIVOT (
[Value]
FOR [VariableName] IN(
[TotalCount],
[ForRecreation],
[IsQualifiedForSeniors],
--...(All the other things i selected in above query)...
)
) as d
select * from #resultTable
The combination of a Realtor- and contentID gives me a set default set of X amount of records. When I choose a Combination which gives me ~4600 records, the execution time is around 250ms. When I execute the sattement with a combination that gives me ~600 record, the execution time is about 20ms.
I would like to know why this is happening. I tried removing all SUM(CASE in the select, I tried removing almost everything from the WHERE-clause, and I tried removing the JOIN. But I keep seeing the huge difference between the resultset of 4600 and 600.
Table variables can perform worse when the number of records is large. Consider using a temporary table instead. See When should I use a table variable vs temporary table in sql server?
Also, consider replacing the UNPIVOT by alternative SQL code. Writing your own TSQL code will give you more control and even increase performance. See for example PIVOT, UNPIVOT and performance
I have a sql server table named Student like below:
I wish to select the students with the highest score from each class, which shall produce the output like this:
Due to some constraint, I can't be sure how many unique class names would exist in the table. My stored procedure is :
create procedure selectBestStudent
as
begin
select Name, max(TestScore)
from [TestDB1].[dbo].[StudentTest]
group by Name
end
But the result is wrong. Any idea?
You can use ROW_NUMBER with a PARTITION BY:
SELECT Name, Class, TestScore
FROM (
SELECT Name, Class, TestScore,
ROW_NUMBER() OVER (PARTITION BY Class
ORDER BY TestScore DESC) AS rn
FROM StudentTest) AS t
WHERE t.rn = 1
ROW_NUMBER enumerates records within each Class partition: the ORDER BY clause guarantees that the record having the greatest TestScore value is assigned a value equal to 1.
Note: To handle ties you can use RANK in place of ROW_NUMBER. This way you can get all students that share the same maximum TestScore for the same Class.
You can also achieve this goal with NOT EXISTS()
SELECT * FROM Student s
WHERE NOT EXISTS(select 1 FROM Student t
where t.class = s.class
and t.testScore > s.testScore)
This will select only those rows that doesn't have a row with a higher value on testScore
I think you will have a problem with the Group By and the MAX() when there are multiple people with the same score in a class.
I solved it with a fetch if you don't know yet what this is, you can look here. It's easier than it looks at the beginning!
I know that might be a horrible way to do it but its's easy to understand and it worked! :D
USE [TestDB]
GO
DECLARE #class char(10), #testscore int;
DECLARE #result Table
(
Name char(10),
Class char(10),
TestScore int
);
-- Get Classes and their Maxima
DECLARE TestScore_cursor CURSOR FOR SELECT [class], MAX([testscore]) FROM [student] GROUP BY [class];
OPEN TestScore_cursor;
-- Perform the first fetch.
FETCH NEXT FROM TestScore_cursor INTO #class, #testscore;
-- Check ##FETCH_STATUS to see if there are any more rows to fetch.
WHILE ##FETCH_STATUS = 0
BEGIN
-- Search Students by Class and Score and add them to tempTable #result
INSERT INTO #result SELECT [name], [class], [testscore] From [student] where [testScore] = #testscore AND [class] = #class;
FETCH NEXT FROM TestScore_cursor INTO #class, #testscore;
END
-- Show the Result
SELECT * FROM #result;
CLOSE TestScore_cursor;
DEALLOCATE TestScore_cursor;
GO
I was looking at different ways of writing a stored procedure to return a "page" of data. This was for use with the ASP ObjectDataSource, but it could be considered a more general problem.
The requirement is to return a subset of the data based on the usual paging parameters; startPageIndex and maximumRows, but also a sortBy parameter to allow the data to be sorted. Also there are some parameters passed in to filter the data on various conditions.
One common way to do this seems to be something like this:
[Method 1]
;WITH stuff AS (
SELECT
CASE
WHEN #SortBy = 'Name' THEN ROW_NUMBER() OVER (ORDER BY Name)
WHEN #SortBy = 'Name DESC' THEN ROW_NUMBER() OVER (ORDER BY Name DESC)
WHEN #SortBy = ...
ELSE ROW_NUMBER() OVER (ORDER BY whatever)
END AS Row,
.,
.,
.,
FROM Table1
INNER JOIN Table2 ...
LEFT JOIN Table3 ...
WHERE ... (lots of things to check)
)
SELECT *
FROM stuff
WHERE (Row > #startRowIndex)
AND (Row <= #startRowIndex + #maximumRows OR #maximumRows <= 0)
ORDER BY Row
One problem with this is that it doesn't give the total count and generally we need another stored procedure for that. This second stored procedure has to replicate the parameter list and the complex WHERE clause. Not nice.
One solution is to append an extra column to the final select list, (SELECT COUNT(*) FROM stuff) AS TotalRows. This gives us the total but repeats it for every row in the result set, which is not ideal.
[Method 2]
An interesting alternative is given here (https://web.archive.org/web/20211020111700/https://www.4guysfromrolla.com/articles/032206-1.aspx) using dynamic SQL. He reckons that the performance is better because the CASE statement in the first solution drags things down. Fair enough, and this solution makes it easy to get the totalRows and slap it into an output parameter. But I hate coding dynamic SQL. All that 'bit of SQL ' + STR(#parm1) +' bit more SQL' gubbins.
[Method 3]
The only way I can find to get what I want, without repeating code which would have to be synchronized, and keeping things reasonably readable is to go back to the "old way" of using a table variable:
DECLARE #stuff TABLE (Row INT, ...)
INSERT INTO #stuff
SELECT
CASE
WHEN #SortBy = 'Name' THEN ROW_NUMBER() OVER (ORDER BY Name)
WHEN #SortBy = 'Name DESC' THEN ROW_NUMBER() OVER (ORDER BY Name DESC)
WHEN #SortBy = ...
ELSE ROW_NUMBER() OVER (ORDER BY whatever)
END AS Row,
.,
.,
.,
FROM Table1
INNER JOIN Table2 ...
LEFT JOIN Table3 ...
WHERE ... (lots of things to check)
SELECT *
FROM stuff
WHERE (Row > #startRowIndex)
AND (Row <= #startRowIndex + #maximumRows OR #maximumRows <= 0)
ORDER BY Row
(Or a similar method using an IDENTITY column on the table variable).
Here I can just add a SELECT COUNT on the table variable to get the totalRows and put it into an output parameter.
I did some tests and with a fairly simple version of the query (no sortBy and no filter), method 1 seems to come up on top (almost twice as quick as the other 2). Then I decided to test probably I needed the complexity and I needed the SQL to be in stored procedures. With this I get method 1 taking nearly twice as long as the other 2 methods. Which seems strange.
Is there any good reason why I shouldn't spurn CTEs and stick with method 3?
UPDATE - 15 March 2012
I tried adapting Method 1 to dump the page from the CTE into a temporary table so that I could extract the TotalRows and then select just the relevant columns for the resultset. This seemed to add significantly to the time (more than I expected). I should add that I'm running this on a laptop with SQL Server Express 2008 (all that I have available) but still the comparison should be valid.
I looked again at the dynamic SQL method. It turns out I wasn't really doing it properly (just concatenating strings together). I set it up as in the documentation for sp_executesql (with a parameter description string and parameter list) and it's much more readable. Also this method runs fastest in my environment. Why that should be still baffles me, but I guess the answer is hinted at in Hogan's comment.
I would most likely split the #SortBy argument into two, #SortColumn and #SortDirection, and use them like this:
…
ROW_NUMBER() OVER (
ORDER BY CASE #SortColumn
WHEN 'Name' THEN Name
WHEN 'OtherName' THEN OtherName
…
END *
CASE #SortDirection
WHEN 'DESC' THEN -1
ELSE 1
END
) AS Row
…
And this is how the TotalRows column could be defined (in the main select):
…
COUNT(*) OVER () AS TotalRows
…
I would definitely want to do a combination of a temp table and NTILE for this sort of approach.
The temp table will allow you to do your complicated series of conditions just once. Because you're only storing the pieces you care about, it also means that when you start doing selects against it further in the procedure, it should have a smaller overall memory usage than if you ran the condition multiple times.
I like NTILE() for this better than ROW_NUMBER() because it's doing the work you're trying to accomplish for you, rather than having additional where conditions to worry about.
The example below is one based off a similar query I'm using as part of a research query; I have an ID I can use that I know will be unique in the results. Using an ID that was an identity column would also be appropriate here, though.
--DECLARES here would be stored procedure parameters
declare #pagesize int, #sortby varchar(25), #page int = 1;
--Create temp with all relevant columns; ID here could be an identity PK to help with paging query below
create table #temp (id int not null primary key clustered, status varchar(50), lastname varchar(100), startdate datetime);
--Insert into #temp based off of your complex conditions, but with no attempt at paging
insert into #temp
(id, status, lastname, startdate)
select id, status, lastname, startdate
from Table1 ...etc.
where ...complicated conditions
SET #pagesize = 50;
SET #page = 5;--OR CAST(#startRowIndex/#pagesize as int)+1
SET #sortby = 'name';
--Only use the id and count to use NTILE
;with paging(id, pagenum, totalrows) as
(
select id,
NTILE((SELECT COUNT(*) cnt FROM #temp)/#pagesize) OVER(ORDER BY CASE WHEN #sortby = 'NAME' THEN lastname ELSE convert(varchar(10), startdate, 112) END),
cnt
FROM #temp
cross apply (SELECT COUNT(*) cnt FROM #temp) total
)
--Use the id to join back to main select
SELECT *
FROM paging
JOIN #temp ON paging.id = #temp.id
WHERE paging.pagenum = #page
--Don't need the drop in the procedure, included here for rerunnability
drop table #temp;
I generally prefer temp tables over table variables in this scenario, largely so that there are definite statistics on the result set you have. (Search for temp table vs table variable and you'll find plenty of examples as to why)
Dynamic SQL would be most useful for handling the sorting method. Using my example, you could do the main query in dynamic SQL and only pull the sort method you want to pull into the OVER().
The example above also does the total in each row of the return set, which as you mentioned was not ideal. You could, instead, have a #totalrows output variable in your procedure and pull it as well as the result set. That would save you the CROSS APPLY that I'm doing above in the paging CTE.
I would create one procedure to stage, sort, and paginate (using NTILE()) a staging table; and a second procedure to retrieve by page. This way you don't have to run the entire main query for each page.
This example queries AdventureWorks.HumanResources.Employee:
--------------------------------------------------------------------------
create procedure dbo.EmployeesByMartialStatus
#MaritalStatus nchar(1)
, #sort varchar(20)
as
-- Init staging table
if exists(
select 1 from sys.objects o
inner join sys.schemas s on s.schema_id=o.schema_id
and s.name='Staging'
and o.name='EmployeesByMartialStatus'
where type='U'
)
drop table Staging.EmployeesByMartialStatus;
-- Populate staging table with sort value
with s as (
select *
, sr=ROW_NUMBER()over(order by case #sort
when 'NationalIDNumber' then NationalIDNumber
when 'ManagerID' then ManagerID
-- plus any other sort conditions
else EmployeeID end)
from AdventureWorks.HumanResources.Employee
where MaritalStatus=#MaritalStatus
)
select *
into #temp
from s;
-- And now pages
declare #RowCount int; select #rowCount=COUNT(*) from #temp;
declare #PageCount int=ceiling(#rowCount/20); --assuming 20 lines/page
select *
, Page=NTILE(#PageCount)over(order by sr)
into Staging.EmployeesByMartialStatus
from #temp;
go
--------------------------------------------------------------------------
-- procedure to retrieve selected pages
create procedure EmployeesByMartialStatus_GetPage
#page int
as
declare #MaxPage int;
select #MaxPage=MAX(Page) from Staging.EmployeesByMartialStatus;
set #page=case when #page not between 1 and #MaxPage then 1 else #page end;
select EmployeeID,NationalIDNumber,ContactID,LoginID,ManagerID
, Title,BirthDate,MaritalStatus,Gender,HireDate,SalariedFlag,VacationHours,SickLeaveHours
, CurrentFlag,rowguid,ModifiedDate
from Staging.EmployeesByMartialStatus
where Page=#page
GO
--------------------------------------------------------------------------
-- Usage
-- Load staging
exec dbo.EmployeesByMartialStatus 'M','NationalIDNumber';
-- Get pages 1 through n
exec dbo.EmployeesByMartialStatus_GetPage 1;
exec dbo.EmployeesByMartialStatus_GetPage 2;
-- ...etc (this would actually be a foreach loop, but that detail is omitted for brevity)
GO
I use this method of using EXEC():
-- SP parameters:
-- #query: Your query as an input parameter
-- #maximumRows: As number of rows per page
-- #startPageIndex: As number of page to filter
-- #sortBy: As a field name or field names with supporting DESC keyword
DECLARE #query nvarchar(max) = 'SELECT * FROM sys.Objects',
#maximumRows int = 8,
#startPageIndex int = 3,
#sortBy as nvarchar(100) = 'name Desc'
SET #query = ';WITH CTE AS (' + #query + ')' +
'SELECT *, (dt.pagingRowNo - 1) / ' + CAST(#maximumRows as nvarchar(10)) + ' + 1 As pagingPageNo' +
', pagingCountRow / ' + CAST(#maximumRows as nvarchar(10)) + ' As pagingCountPage ' +
', (dt.pagingRowNo - 1) % ' + CAST(#maximumRows as nvarchar(10)) + ' + 1 As pagingRowInPage ' +
'FROM ( SELECT *, ROW_NUMBER() OVER (ORDER BY ' + #sortBy + ') As pagingRowNo, COUNT(*) OVER () AS pagingCountRow ' +
'FROM CTE) dt ' +
'WHERE (dt.pagingRowNo - 1) / ' + CAST(#maximumRows as nvarchar(10)) + ' + 1 = ' + CAST(#startPageIndex as nvarchar(10))
EXEC(#query)
At result-set after query result columns:
Note:
I add some extra columns that you can remove them:
pagingRowNo : The row number
pagingCountRow : The total number of rows
pagingPageNo : The current page number
pagingCountPage : The total number of pages
pagingRowInPage : The row number that started with 1 in this page