Related
I've created a stored procedure that filters and paginates for a DataTable.
Problem: I need to set an OUTPUT variable for #TotalRecords found before an OFFSET occurs, otherwise it sets #TotalRecord to #RecordPerPage.
I've messed around with CTE's and also simply trying this:
SELECT *, #TotalRecord = COUNT(1)
FROM dbo
But that doesn't work either.
Here is my stored procedure, with most of the stuff pulled out:
ALTER PROCEDURE [dbo].[SearchErrorReports]
#FundNumber varchar(50) = null,
#ProfitSelected bit = 0,
#SortColumnName varchar(30) = null,
#SortDirection varchar(10) = null,
#StartIndex int = 0,
#RecordPerPage int = null,
#TotalRecord INT = 0 OUTPUT --NEED TO SET THIS BEFORE OFFSET!
AS
BEGIN
SET NOCOUNT ON;
SELECT *
FROM
(SELECT *
FROM dbo.View
WHERE (#ProfitSelected = 1 AND Profit = 1)) AS ERP
WHERE
((#FundNumber IS NULL OR #FundNumber = '')
OR (ERP.FundNumber LIKE '%' + #FundNumber + '%'))
ORDER BY
CASE
WHEN #SortColumnName = 'FundNumber' AND #SortDirection = 'asc'
THEN ERP.FundNumber
END ASC,
CASE
WHEN #SortColumnName = 'FundNumber' AND #SortDirection = 'desc'
THEN ERP.FundNumber
END DESC
OFFSET #StartIndex ROWS
FETCH NEXT #RecordPerPage ROWS ONLY
Thank you in advance!
You could try something like this:
create a CTE that gets the data you want to return
include a COUNT(*) OVER() in there to get the total count of rows
return just a subset (based on your OFFSET .. FETCH NEXT) from the CTE
So your code would look something along those lines:
-- CTE definition - call it whatever you like
WITH BaseData AS
(
SELECT
-- select all the relevant columns you need
p.ProductID,
p.ProductName,
-- using COUNT(*) OVER() returns the total count over all rows
TotalCount = COUNT(*) OVER()
FROM
dbo.Products p
)
-- now select from the CTE - using OFFSET/FETCH NEXT, get only those rows you
-- want - but the "TotalCount" column still contains the total count - before
-- the OFFSET/FETCH
SELECT *
FROM BaseData
ORDER BY ProductID
OFFSET 20 ROWS FETCH NEXT 15 ROWS ONLY
As a habit, I prefer non-null entries before possible null. I did not reference those in my response below, and limited a working example to just the two inputs you are most concerned with.
I believe there could be some more clean ways to apply your local variables to filter the query results without having to perform an offset. You could return to a temp table or a permanent usage table that cleans itself up and use IDs that aren't returned as a way to set pages. Smoother, with less fuss.
However, I understand that isn't always feasible, and I become frustrated myself with those attempting to solve your use case for you without attempting to answer the question. Quite often there are multiple ways to tackle any issue. Your job is to decide which one is best in your scenario. Our job is to help you figure out the script.
With that said, here's a potential solution using dynamic SQL.
I'm a huge believer in dynamic SQL, and use it extensively for user based table control and ease of ETL mapping control.
use TestCatalog;
set nocount on;
--Builds a temp table, just for test purposes
drop table if exists ##TestOffset;
create table ##TestOffset
(
Id int identity(1,1)
, RandomNumber decimal (10,7)
);
--Inserts 1000 random numbers between 0 and 100
while (select count(*) from ##TestOffset) < 1000
begin
insert into ##TestOffset
(RandomNumber)
values
(RAND()*100)
end;
set nocount off;
go
create procedure dbo.TestOffsetProc
#StartIndex int = null --I'll reference this like a page number below
, #RecordsPerPage int = null
as
begin
declare #MaxRows int = 30; --your front end will probably manage this, but don't trust it. I personally would store this on a table against each display so it can also be returned dynamically with less manual intrusion to this procedure.
declare #FirstRow int;
--Quick entry to ensure your record count returned doesn't excede max allowed.
if #RecordsPerPage is null or #RecordsPerPage > #MaxRows
begin
set #RecordsPerPage = #MaxRows
end;
--Same here, making sure not to return NULL to your dynamic statement. If null is returned from any variable, the entire statement will become null.
if #StartIndex is null
begin
set #StartIndex = 0
end;
set #FirstRow = #StartIndex * #RecordsPerPage
declare #Sql nvarchar(2000) = 'select
tos.*
from ##TestOffset as tos
order by tos.RandomNumber desc
offset ' + convert(nvarchar,#FirstRow) + ' rows
fetch next ' + convert(nvarchar,#RecordsPerPage) + ' rows only'
exec (#Sql);
end
go
exec dbo.TestOffsetProc;
drop table ##TestOffset;
drop procedure dbo.TestOffsetProc;
How can one call a stored procedure for each row in a table, where the columns of a row are input parameters to the sp without using a Cursor?
Generally speaking I always look for a set based approach (sometimes at the expense of changing the schema).
However, this snippet does have its place..
-- Declare & init (2008 syntax)
DECLARE #CustomerID INT = 0
-- Iterate over all customers
WHILE (1 = 1)
BEGIN
-- Get next customerId
SELECT TOP 1 #CustomerID = CustomerID
FROM Sales.Customer
WHERE CustomerID > #CustomerId
ORDER BY CustomerID
-- Exit loop if no more customers
IF ##ROWCOUNT = 0 BREAK;
-- call your sproc
EXEC dbo.YOURSPROC #CustomerId
END
You could do something like this: order your table by e.g. CustomerID (using the AdventureWorks Sales.Customer sample table), and iterate over those customers using a WHILE loop:
-- define the last customer ID handled
DECLARE #LastCustomerID INT
SET #LastCustomerID = 0
-- define the customer ID to be handled now
DECLARE #CustomerIDToHandle INT
-- select the next customer to handle
SELECT TOP 1 #CustomerIDToHandle = CustomerID
FROM Sales.Customer
WHERE CustomerID > #LastCustomerID
ORDER BY CustomerID
-- as long as we have customers......
WHILE #CustomerIDToHandle IS NOT NULL
BEGIN
-- call your sproc
-- set the last customer handled to the one we just handled
SET #LastCustomerID = #CustomerIDToHandle
SET #CustomerIDToHandle = NULL
-- select the next customer to handle
SELECT TOP 1 #CustomerIDToHandle = CustomerID
FROM Sales.Customer
WHERE CustomerID > #LastCustomerID
ORDER BY CustomerID
END
That should work with any table as long as you can define some kind of an ORDER BY on some column.
DECLARE #SQL varchar(max)=''
-- MyTable has fields fld1 & fld2
Select #SQL = #SQL + 'exec myproc ' + convert(varchar(10),fld1) + ','
+ convert(varchar(10),fld2) + ';'
From MyTable
EXEC (#SQL)
Ok, so I would never put such code into production, but it does satisfy your requirements.
I'd use the accepted answer, but another possibility is to use a table variable to hold a numbered set of values (in this case just the ID field of a table) and loop through those by Row Number with a JOIN to the table to retrieve whatever you need for the action within the loop.
DECLARE #RowCnt int; SET #RowCnt = 0 -- Loop Counter
-- Use a table variable to hold numbered rows containg MyTable's ID values
DECLARE #tblLoop TABLE (RowNum int IDENTITY (1, 1) Primary key NOT NULL,
ID INT )
INSERT INTO #tblLoop (ID) SELECT ID FROM MyTable
-- Vars to use within the loop
DECLARE #Code NVarChar(10); DECLARE #Name NVarChar(100);
WHILE #RowCnt < (SELECT COUNT(RowNum) FROM #tblLoop)
BEGIN
SET #RowCnt = #RowCnt + 1
-- Do what you want here with the data stored in tblLoop for the given RowNum
SELECT #Code=Code, #Name=LongName
FROM MyTable INNER JOIN #tblLoop tL on MyTable.ID=tL.ID
WHERE tl.RowNum=#RowCnt
PRINT Convert(NVarChar(10),#RowCnt) +' '+ #Code +' '+ #Name
END
Marc's answer is good (I'd comment on it if I could work out how to!)
Just thought I'd point out that it may be better to change the loop so the SELECT only exists once (in a real case where I needed to do this, the SELECT was quite complex, and writing it twice was a risky maintenance issue).
-- define the last customer ID handled
DECLARE #LastCustomerID INT
SET #LastCustomerID = 0
-- define the customer ID to be handled now
DECLARE #CustomerIDToHandle INT
SET #CustomerIDToHandle = 1
-- as long as we have customers......
WHILE #LastCustomerID <> #CustomerIDToHandle
BEGIN
SET #LastCustomerId = #CustomerIDToHandle
-- select the next customer to handle
SELECT TOP 1 #CustomerIDToHandle = CustomerID
FROM Sales.Customer
WHERE CustomerID > #LastCustomerId
ORDER BY CustomerID
IF #CustomerIDToHandle <> #LastCustomerID
BEGIN
-- call your sproc
END
END
If you can turn the stored procedure into a function that returns a table, then you can use cross-apply.
For example, say you have a table of customers, and you want to compute the sum of their orders, you would create a function that took a CustomerID and returned the sum.
And you could do this:
SELECT CustomerID, CustomerSum.Total
FROM Customers
CROSS APPLY ufn_ComputeCustomerTotal(Customers.CustomerID) AS CustomerSum
Where the function would look like:
CREATE FUNCTION ComputeCustomerTotal
(
#CustomerID INT
)
RETURNS TABLE
AS
RETURN
(
SELECT SUM(CustomerOrder.Amount) AS Total FROM CustomerOrder WHERE CustomerID = #CustomerID
)
Obviously, the example above could be done without a user defined function in a single query.
The drawback is that functions are very limited - many of the features of a stored procedure are not available in a user-defined function, and converting a stored procedure to a function does not always work.
For SQL Server 2005 onwards, you can do this with CROSS APPLY and a table-valued function.
Using CROSS APPLY in SQL Server 2005
Just for clarity, I'm referring to those cases where the stored procedure can be converted into a table valued function.
This is a variation on the answers already provided, but should be better performing because it doesn't require ORDER BY, COUNT or MIN/MAX. The only disadvantage with this approach is that you have to create a temp table to hold all the Ids (the assumption is that you have gaps in your list of CustomerIDs).
That said, I agree with #Mark Powell though that, generally speaking, a set based approach should still be better.
DECLARE #tmp table (Id INT IDENTITY(1,1) PRIMARY KEY NOT NULL, CustomerID INT NOT NULL)
DECLARE #CustomerId INT
DECLARE #Id INT = 0
INSERT INTO #tmp SELECT CustomerId FROM Sales.Customer
WHILE (1=1)
BEGIN
SELECT #CustomerId = CustomerId, #Id = Id
FROM #tmp
WHERE Id = #Id + 1
IF ##rowcount = 0 BREAK;
-- call your sproc
EXEC dbo.YOURSPROC #CustomerId;
END
This is a variation of n3rds solution above. No sorting by using ORDER BY is needed, as MIN() is used.
Remember that CustomerID (or whatever other numerical column you use for progress) must have a unique constraint. Furthermore, to make it as fast as possible CustomerID must be indexed on.
-- Declare & init
DECLARE #CustomerID INT = (SELECT MIN(CustomerID) FROM Sales.Customer); -- First ID
DECLARE #Data1 VARCHAR(200);
DECLARE #Data2 VARCHAR(200);
-- Iterate over all customers
WHILE #CustomerID IS NOT NULL
BEGIN
-- Get data based on ID
SELECT #Data1 = Data1, #Data2 = Data2
FROM Sales.Customer
WHERE [ID] = #CustomerID ;
-- call your sproc
EXEC dbo.YOURSPROC #Data1, #Data2
-- Get next customerId
SELECT #CustomerID = MIN(CustomerID)
FROM Sales.Customer
WHERE CustomerID > #CustomerId
END
I use this approach on some varchars I need to look over, by putting them in a temporary table first, to give them an ID.
If you don't what to use a cursor I think you'll have to do it externally (get the table, and then run for each statement and each time call the sp)
it Is the same as using a cursor, but only outside SQL.
Why won't you use a cursor ?
I usually do it this way when it's a quite a few rows:
Select all sproc parameters in a dataset with SQL Management Studio
Right-click -> Copy
Paste in to excel
Create single-row sql statements with a formula like '="EXEC schema.mysproc #param=" & A2' in a new excel column. (Where A2 is your excel column containing the parameter)
Copy the list of excel statements into a new query in SQL Management Studio and execute.
Done.
(On larger datasets i'd use one of the solutions mentioned above though).
DELIMITER //
CREATE PROCEDURE setFakeUsers (OUT output VARCHAR(100))
BEGIN
-- define the last customer ID handled
DECLARE LastGameID INT;
DECLARE CurrentGameID INT;
DECLARE userID INT;
SET #LastGameID = 0;
-- define the customer ID to be handled now
SET #userID = 0;
-- select the next game to handle
SELECT #CurrentGameID = id
FROM online_games
WHERE id > LastGameID
ORDER BY id LIMIT 0,1;
-- as long as we have customers......
WHILE (#CurrentGameID IS NOT NULL)
DO
-- call your sproc
-- set the last customer handled to the one we just handled
SET #LastGameID = #CurrentGameID;
SET #CurrentGameID = NULL;
-- select the random bot
SELECT #userID = userID
FROM users
WHERE FIND_IN_SET('bot',baseInfo)
ORDER BY RAND() LIMIT 0,1;
-- update the game
UPDATE online_games SET userID = #userID WHERE id = #CurrentGameID;
-- select the next game to handle
SELECT #CurrentGameID = id
FROM online_games
WHERE id > LastGameID
ORDER BY id LIMIT 0,1;
END WHILE;
SET output = "done";
END;//
CALL setFakeUsers(#status);
SELECT #status;
A better solution for this is to
Copy/past code of Stored Procedure
Join that code with the table for which you want to run it again (for each row)
This was you get a clean table-formatted output. While if you run SP for every row, you get a separate query result for each iteration which is ugly.
In case the order is important
--declare counter
DECLARE #CurrentRowNum BIGINT = 0;
--Iterate over all rows in [DataTable]
WHILE (1 = 1)
BEGIN
--Get next row by number of row
SELECT TOP 1 #CurrentRowNum = extendedData.RowNum
--here also you can store another values
--for following usage
--#MyVariable = extendedData.Value
FROM (
SELECT
data.*
,ROW_NUMBER() OVER(ORDER BY (SELECT 0)) RowNum
FROM [DataTable] data
) extendedData
WHERE extendedData.RowNum > #CurrentRowNum
ORDER BY extendedData.RowNum
--Exit loop if no more rows
IF ##ROWCOUNT = 0 BREAK;
--call your sproc
--EXEC dbo.YOURSPROC #MyVariable
END
I had some production code that could only handle 20 employees at a time, below is the framework for the code. I just copied the production code and removed stuff below.
ALTER procedure GetEmployees
#ClientId varchar(50)
as
begin
declare #EEList table (employeeId varchar(50));
declare #EE20 table (employeeId varchar(50));
insert into #EEList select employeeId from Employee where (ClientId = #ClientId);
-- Do 20 at a time
while (select count(*) from #EEList) > 0
BEGIN
insert into #EE20 select top 20 employeeId from #EEList;
-- Call sp here
delete #EEList where employeeId in (select employeeId from #EE20)
delete #EE20;
END;
RETURN
end
I had a situation where I needed to perform a series of operations on a result set (table). The operations are all set operations, so its not an issue, but...
I needed to do this in multiple places. So putting the relevant pieces in a table type, then populating a table variable w/ each result set allows me to call the sp and repeat the operations each time i need to .
While this does not address the exact question he asks, it does address how to perform an operation on all rows of a table without using a cursor.
#Johannes offers no insight into his motivation , so this may or may not help him.
my research led me to this well written article which served as a basis for my solution
https://codingsight.com/passing-data-table-as-parameter-to-stored-procedures/
Here is the setup
drop type if exists cpRootMapType
go
create type cpRootMapType as Table(
RootId1 int
, RootId2 int
)
go
drop procedure if exists spMapRoot2toRoot1
go
create procedure spMapRoot2toRoot1
(
#map cpRootMapType Readonly
)
as
update linkTable set root = root1
from linktable lt
join #map m on lt.root = root2
update comments set root = root1
from comments c
join #map m on c.root = root2
-- ever growing list of places this map would need to be applied....
-- now consolidated into one place
here is the implementation
... populate #matches
declare #map cpRootMapType
insert #map select rootid1, rootid2 from #matches
exec spMapRoot2toRoot1 #map
I like to do something similar to this (though it is still very similar to using a cursor)
[code]
-- Table variable to hold list of things that need looping
DECLARE #holdStuff TABLE (
id INT IDENTITY(1,1) ,
isIterated BIT DEFAULT 0 ,
someInt INT ,
someBool BIT ,
otherStuff VARCHAR(200)
)
-- Populate your #holdStuff with... stuff
INSERT INTO #holdStuff (
someInt ,
someBool ,
otherStuff
)
SELECT
1 , -- someInt - int
1 , -- someBool - bit
'I like turtles' -- otherStuff - varchar(200)
UNION ALL
SELECT
42 , -- someInt - int
0 , -- someBool - bit
'something profound' -- otherStuff - varchar(200)
-- Loop tracking variables
DECLARE #tableCount INT
SET #tableCount = (SELECT COUNT(1) FROM [#holdStuff])
DECLARE #loopCount INT
SET #loopCount = 1
-- While loop variables
DECLARE #id INT
DECLARE #someInt INT
DECLARE #someBool BIT
DECLARE #otherStuff VARCHAR(200)
-- Loop through item in #holdStuff
WHILE (#loopCount <= #tableCount)
BEGIN
-- Increment the loopCount variable
SET #loopCount = #loopCount + 1
-- Grab the top unprocessed record
SELECT TOP 1
#id = id ,
#someInt = someInt ,
#someBool = someBool ,
#otherStuff = otherStuff
FROM #holdStuff
WHERE isIterated = 0
-- Update the grabbed record to be iterated
UPDATE #holdAccounts
SET isIterated = 1
WHERE id = #id
-- Execute your stored procedure
EXEC someRandomSp #someInt, #someBool, #otherStuff
END
[/code]
Note that you don't need the identity or the isIterated column on your temp/variable table, i just prefer to do it this way so i don't have to delete the top record from the collection as i iterate through the loop.
I am trying to Insert data in a table named "Candidate_Post_Info_Table_ChangeLogs" whenever a record is updated in another table named "Candidate_Personal_Info_Table". my code works fine whenever a single record is updated but when i try to updated multiple rows it gives error:
"Sub query returned more then 1 value".
Following is my code :
ALTER TRIGGER [dbo].[Candidate_PostInfo_UPDATE]
ON [dbo].[Candidate_Post_Info_Table]
AFTER UPDATE
AS
BEGIN
IF ##ROWCOUNT = 0
RETURN
DECLARE #Candidate_Post_ID int
DECLARE #Candidate_ID varchar(50)
DECLARE #Action VARCHAR(50)
DECLARE #OldValue VARCHAR(MAX)
DECLARE #NewValue VARCHAR(MAX)
DECLARE #Admin_id int
IF UPDATE(Verified)
BEGIN
SET #Action = 'Changed Verification Status'
SET #Candidate_Post_ID = (Select ID From inserted)
SET #Candidate_ID = (Select Identity_Number from inserted)
SET #NewValue = (Select Verified From inserted)
SET #OldValue = (Select Verified From deleted)
IF(#NewValue != #OldValue)
BEGIN
INSERT INTO Candidate_Post_Info_Table_ChangeLogs(Candidate_Post_ID, Candidate_ID, Change_DateTime, action, NewValue, OldValue, Admin_ID)
VALUES(#Candidate_Post_ID, #Candidate_ID, GETDATE(), #Action, #NewValue, #OldValue, '1')
END
END
END
i have searched stack overflow for this issue but couldn't get any related answer specific to this scenario.
When you insert/update multiple rows into a table, the Inserted temporary table used by the system holds all of the values from all of the rows that were inserted or updated.
Therefore, if you do an update to 6 rows, the Inserted table will also have 6 rows, and doing something like this:
SET #Candidate_Post_ID = (Select ID From inserted)
Will return an error, just the same as doing this:
SET #Candidate_Post_ID = (SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6)
From the looks of things, you tried to do this with an iterative approach. Set-based is better. Maybe consider doing it like this in the body of your TRIGGER (without all of the parameters...):
IF UPDATE(Verified)
BEGIN
INSERT INTO Candidate_Post_Info_Table_ChangeLogs
(
Candidate_Post_ID
,Candidate_ID
,Change_DateTime
,action
,NewValue
,OldValue
,Admin_ID
)
SELECT
I.ID
,I.Identity_Number
,GETDATE()
,'Changed Verification Status'
,I.Verified
,O.Verified
,'1'
FROM Inserted I
INNER JOIN Deleted O
ON I.ID = O.ID -- Check this condition to make sure it's a unique join per row
WHERE I.Verified <> O.Verified
END
A similar case was solved in the following thread using cursors.... please check it
SQL Server A trigger to work on multiple row inserts
Also the below thread gives the solution based on set based approach
SQL Server - Rewrite trigger to avoid cursor based approach
*Both the above threads are from stack overflow...
I am using SQL Server 2008 and running the following stored procedure that needs to "clean" a 70 mill table from about 50 mill rows to another table, the id_col is integer (primary identity key)
According to the last running I made it is working good but it is expected to last for about 200 days:
SET NOCOUNT ON
-- define the last ID handled
DECLARE #LastID integer
SET #LastID = 0
declare #tempDate datetime
set #tempDate = dateadd(dd,-20,getdate())
-- define the ID to be handled now
DECLARE #IDToHandle integer
DECLARE #iCounter integer
DECLARE #watch1 nvarchar(50)
DECLARE #watch2 nvarchar(50)
set #iCounter = 0
-- select the next to handle
SELECT TOP 1 #IDToHandle = id_col
FROM MAIN_TABLE
WHERE id_col> #LastID and DATEDIFF(DD,someDateCol,otherDateCol) < 1
and datediff(dd,someDateCol,#tempDate) > 0 and (some_other_int_col = 1745 or some_other_int_col = 1548 or some_other_int_col = 4785)
ORDER BY id_col
-- as long as we have s......
WHILE #IDToHandle IS NOT NULL
BEGIN
IF ((select count(1) from SOME_OTHER_TABLE_THAT_CONTAINS_20k_ROWS where some_int_col = #IDToHandle) = 0 and (select count(1) from A_70k_rows_table where some_int_col =#IDToHandle )=0)
BEGIN
INSERT INTO SECONDERY_TABLE
SELECT col1,col2,col3.....
FROM MAIN_TABLE WHERE id_col = #IDToHandle
EXEC [dbo].[DeleteByID] #ID = #IDToHandle --deletes the row from 2 other tables that is related to the MAIN_TABLE and than from the MAIN_TABLE
set #iCounter = #iCounter +1
END
IF (#iCounter % 1000 = 0)
begin
set #watch1 = 'iCounter - ' + CAST(#iCounter AS VARCHAR)
set #watch2 = 'IDToHandle - '+ CAST(#IDToHandle AS VARCHAR)
raiserror ( #watch1, 10,1) with nowait
raiserror (#watch2, 10,1) with nowait
end
-- set the last handled to the one we just handled
SET #LastID = #IDToHandle
SET #IDToHandle = NULL
-- select the next to handle
SELECT TOP 1 #IDToHandle = id_col
FROM MAIN_TABLE
WHERE id_col> #LastID and DATEDIFF(DD,someDateCol,otherDateCol) < 1
and datediff(dd,someDateCol,#tempDate) > 0 and (some_other_int_col = 1745 or some_other_int_col = 1548 or some_other_int_col = 4785)
ORDER BY id_col
END
Any ideas or directions to improve this procedure run-time will be welcomed
Yes, try this:
Declare #Ids Table (id int Primary Key not Null)
Insert #Ids(id)
Select id_col
From MAIN_TABLE m
Where someDateCol >= otherDateCol
And someDateCol < #tempDate -- If there are times in these datetime fields,
-- then you may need to modify this condition.
And some_other_int_col In (1745, 1548, 4785)
And Not exists (Select * from SOME_OTHER_TABLE_THAT_CONTAINS_20k_ROWS
Where some_int_col = m.id_col)
And Not Exists (Select * From A_70k_rows_table
Where some_int_col = m.id_col)
Select id from #Ids -- this to confirm above code generates the correct list of Ids
return -- this line to stop (Not do insert/deletes) until you have verified #Ids is correct
-- Once you have verified that above #Ids is correctly populated,
-- then delete or comment out the select and return lines above so insert runs.
Begin Transaction
Delete OT -- eliminate row-by-row call to second stored proc
From OtherTable ot
Join MAIN_TABLE m On m.id_col = ot.FKCol
Join #Ids i On i.Id = m.id_col
Insert SECONDERY_TABLE(col1, col2, etc.)
Select col1,col2,col3.....
FROM MAIN_TABLE m Join #Ids i On i.Id = m.id_col
Delete m -- eliminate row-by-row call to second stored proc
FROM MAIN_TABLE m
Join #Ids i On i.Id = m.id_col
Commit Transaction
Explaanation.
You had numerous filtering conditions that were not SARGable, i.e., they would force a complete table scan for every iteration of your loop, instead of being able to use any existing index. Always try to avoid filter conditions that apply processing logic to a table column value before comparing it to some other value. This eliminates the opportunity for the query optimizer to use an index.
You were executing the inserts one at a time... Way better to generate a list of PK Ids that need to be processed (all at once) and then do all the inserts at once, in one statement.
How can one call a stored procedure for each row in a table, where the columns of a row are input parameters to the sp without using a Cursor?
Generally speaking I always look for a set based approach (sometimes at the expense of changing the schema).
However, this snippet does have its place..
-- Declare & init (2008 syntax)
DECLARE #CustomerID INT = 0
-- Iterate over all customers
WHILE (1 = 1)
BEGIN
-- Get next customerId
SELECT TOP 1 #CustomerID = CustomerID
FROM Sales.Customer
WHERE CustomerID > #CustomerId
ORDER BY CustomerID
-- Exit loop if no more customers
IF ##ROWCOUNT = 0 BREAK;
-- call your sproc
EXEC dbo.YOURSPROC #CustomerId
END
You could do something like this: order your table by e.g. CustomerID (using the AdventureWorks Sales.Customer sample table), and iterate over those customers using a WHILE loop:
-- define the last customer ID handled
DECLARE #LastCustomerID INT
SET #LastCustomerID = 0
-- define the customer ID to be handled now
DECLARE #CustomerIDToHandle INT
-- select the next customer to handle
SELECT TOP 1 #CustomerIDToHandle = CustomerID
FROM Sales.Customer
WHERE CustomerID > #LastCustomerID
ORDER BY CustomerID
-- as long as we have customers......
WHILE #CustomerIDToHandle IS NOT NULL
BEGIN
-- call your sproc
-- set the last customer handled to the one we just handled
SET #LastCustomerID = #CustomerIDToHandle
SET #CustomerIDToHandle = NULL
-- select the next customer to handle
SELECT TOP 1 #CustomerIDToHandle = CustomerID
FROM Sales.Customer
WHERE CustomerID > #LastCustomerID
ORDER BY CustomerID
END
That should work with any table as long as you can define some kind of an ORDER BY on some column.
DECLARE #SQL varchar(max)=''
-- MyTable has fields fld1 & fld2
Select #SQL = #SQL + 'exec myproc ' + convert(varchar(10),fld1) + ','
+ convert(varchar(10),fld2) + ';'
From MyTable
EXEC (#SQL)
Ok, so I would never put such code into production, but it does satisfy your requirements.
I'd use the accepted answer, but another possibility is to use a table variable to hold a numbered set of values (in this case just the ID field of a table) and loop through those by Row Number with a JOIN to the table to retrieve whatever you need for the action within the loop.
DECLARE #RowCnt int; SET #RowCnt = 0 -- Loop Counter
-- Use a table variable to hold numbered rows containg MyTable's ID values
DECLARE #tblLoop TABLE (RowNum int IDENTITY (1, 1) Primary key NOT NULL,
ID INT )
INSERT INTO #tblLoop (ID) SELECT ID FROM MyTable
-- Vars to use within the loop
DECLARE #Code NVarChar(10); DECLARE #Name NVarChar(100);
WHILE #RowCnt < (SELECT COUNT(RowNum) FROM #tblLoop)
BEGIN
SET #RowCnt = #RowCnt + 1
-- Do what you want here with the data stored in tblLoop for the given RowNum
SELECT #Code=Code, #Name=LongName
FROM MyTable INNER JOIN #tblLoop tL on MyTable.ID=tL.ID
WHERE tl.RowNum=#RowCnt
PRINT Convert(NVarChar(10),#RowCnt) +' '+ #Code +' '+ #Name
END
Marc's answer is good (I'd comment on it if I could work out how to!)
Just thought I'd point out that it may be better to change the loop so the SELECT only exists once (in a real case where I needed to do this, the SELECT was quite complex, and writing it twice was a risky maintenance issue).
-- define the last customer ID handled
DECLARE #LastCustomerID INT
SET #LastCustomerID = 0
-- define the customer ID to be handled now
DECLARE #CustomerIDToHandle INT
SET #CustomerIDToHandle = 1
-- as long as we have customers......
WHILE #LastCustomerID <> #CustomerIDToHandle
BEGIN
SET #LastCustomerId = #CustomerIDToHandle
-- select the next customer to handle
SELECT TOP 1 #CustomerIDToHandle = CustomerID
FROM Sales.Customer
WHERE CustomerID > #LastCustomerId
ORDER BY CustomerID
IF #CustomerIDToHandle <> #LastCustomerID
BEGIN
-- call your sproc
END
END
If you can turn the stored procedure into a function that returns a table, then you can use cross-apply.
For example, say you have a table of customers, and you want to compute the sum of their orders, you would create a function that took a CustomerID and returned the sum.
And you could do this:
SELECT CustomerID, CustomerSum.Total
FROM Customers
CROSS APPLY ufn_ComputeCustomerTotal(Customers.CustomerID) AS CustomerSum
Where the function would look like:
CREATE FUNCTION ComputeCustomerTotal
(
#CustomerID INT
)
RETURNS TABLE
AS
RETURN
(
SELECT SUM(CustomerOrder.Amount) AS Total FROM CustomerOrder WHERE CustomerID = #CustomerID
)
Obviously, the example above could be done without a user defined function in a single query.
The drawback is that functions are very limited - many of the features of a stored procedure are not available in a user-defined function, and converting a stored procedure to a function does not always work.
For SQL Server 2005 onwards, you can do this with CROSS APPLY and a table-valued function.
Using CROSS APPLY in SQL Server 2005
Just for clarity, I'm referring to those cases where the stored procedure can be converted into a table valued function.
This is a variation on the answers already provided, but should be better performing because it doesn't require ORDER BY, COUNT or MIN/MAX. The only disadvantage with this approach is that you have to create a temp table to hold all the Ids (the assumption is that you have gaps in your list of CustomerIDs).
That said, I agree with #Mark Powell though that, generally speaking, a set based approach should still be better.
DECLARE #tmp table (Id INT IDENTITY(1,1) PRIMARY KEY NOT NULL, CustomerID INT NOT NULL)
DECLARE #CustomerId INT
DECLARE #Id INT = 0
INSERT INTO #tmp SELECT CustomerId FROM Sales.Customer
WHILE (1=1)
BEGIN
SELECT #CustomerId = CustomerId, #Id = Id
FROM #tmp
WHERE Id = #Id + 1
IF ##rowcount = 0 BREAK;
-- call your sproc
EXEC dbo.YOURSPROC #CustomerId;
END
This is a variation of n3rds solution above. No sorting by using ORDER BY is needed, as MIN() is used.
Remember that CustomerID (or whatever other numerical column you use for progress) must have a unique constraint. Furthermore, to make it as fast as possible CustomerID must be indexed on.
-- Declare & init
DECLARE #CustomerID INT = (SELECT MIN(CustomerID) FROM Sales.Customer); -- First ID
DECLARE #Data1 VARCHAR(200);
DECLARE #Data2 VARCHAR(200);
-- Iterate over all customers
WHILE #CustomerID IS NOT NULL
BEGIN
-- Get data based on ID
SELECT #Data1 = Data1, #Data2 = Data2
FROM Sales.Customer
WHERE [ID] = #CustomerID ;
-- call your sproc
EXEC dbo.YOURSPROC #Data1, #Data2
-- Get next customerId
SELECT #CustomerID = MIN(CustomerID)
FROM Sales.Customer
WHERE CustomerID > #CustomerId
END
I use this approach on some varchars I need to look over, by putting them in a temporary table first, to give them an ID.
If you don't what to use a cursor I think you'll have to do it externally (get the table, and then run for each statement and each time call the sp)
it Is the same as using a cursor, but only outside SQL.
Why won't you use a cursor ?
I usually do it this way when it's a quite a few rows:
Select all sproc parameters in a dataset with SQL Management Studio
Right-click -> Copy
Paste in to excel
Create single-row sql statements with a formula like '="EXEC schema.mysproc #param=" & A2' in a new excel column. (Where A2 is your excel column containing the parameter)
Copy the list of excel statements into a new query in SQL Management Studio and execute.
Done.
(On larger datasets i'd use one of the solutions mentioned above though).
DELIMITER //
CREATE PROCEDURE setFakeUsers (OUT output VARCHAR(100))
BEGIN
-- define the last customer ID handled
DECLARE LastGameID INT;
DECLARE CurrentGameID INT;
DECLARE userID INT;
SET #LastGameID = 0;
-- define the customer ID to be handled now
SET #userID = 0;
-- select the next game to handle
SELECT #CurrentGameID = id
FROM online_games
WHERE id > LastGameID
ORDER BY id LIMIT 0,1;
-- as long as we have customers......
WHILE (#CurrentGameID IS NOT NULL)
DO
-- call your sproc
-- set the last customer handled to the one we just handled
SET #LastGameID = #CurrentGameID;
SET #CurrentGameID = NULL;
-- select the random bot
SELECT #userID = userID
FROM users
WHERE FIND_IN_SET('bot',baseInfo)
ORDER BY RAND() LIMIT 0,1;
-- update the game
UPDATE online_games SET userID = #userID WHERE id = #CurrentGameID;
-- select the next game to handle
SELECT #CurrentGameID = id
FROM online_games
WHERE id > LastGameID
ORDER BY id LIMIT 0,1;
END WHILE;
SET output = "done";
END;//
CALL setFakeUsers(#status);
SELECT #status;
A better solution for this is to
Copy/past code of Stored Procedure
Join that code with the table for which you want to run it again (for each row)
This was you get a clean table-formatted output. While if you run SP for every row, you get a separate query result for each iteration which is ugly.
In case the order is important
--declare counter
DECLARE #CurrentRowNum BIGINT = 0;
--Iterate over all rows in [DataTable]
WHILE (1 = 1)
BEGIN
--Get next row by number of row
SELECT TOP 1 #CurrentRowNum = extendedData.RowNum
--here also you can store another values
--for following usage
--#MyVariable = extendedData.Value
FROM (
SELECT
data.*
,ROW_NUMBER() OVER(ORDER BY (SELECT 0)) RowNum
FROM [DataTable] data
) extendedData
WHERE extendedData.RowNum > #CurrentRowNum
ORDER BY extendedData.RowNum
--Exit loop if no more rows
IF ##ROWCOUNT = 0 BREAK;
--call your sproc
--EXEC dbo.YOURSPROC #MyVariable
END
I had some production code that could only handle 20 employees at a time, below is the framework for the code. I just copied the production code and removed stuff below.
ALTER procedure GetEmployees
#ClientId varchar(50)
as
begin
declare #EEList table (employeeId varchar(50));
declare #EE20 table (employeeId varchar(50));
insert into #EEList select employeeId from Employee where (ClientId = #ClientId);
-- Do 20 at a time
while (select count(*) from #EEList) > 0
BEGIN
insert into #EE20 select top 20 employeeId from #EEList;
-- Call sp here
delete #EEList where employeeId in (select employeeId from #EE20)
delete #EE20;
END;
RETURN
end
I had a situation where I needed to perform a series of operations on a result set (table). The operations are all set operations, so its not an issue, but...
I needed to do this in multiple places. So putting the relevant pieces in a table type, then populating a table variable w/ each result set allows me to call the sp and repeat the operations each time i need to .
While this does not address the exact question he asks, it does address how to perform an operation on all rows of a table without using a cursor.
#Johannes offers no insight into his motivation , so this may or may not help him.
my research led me to this well written article which served as a basis for my solution
https://codingsight.com/passing-data-table-as-parameter-to-stored-procedures/
Here is the setup
drop type if exists cpRootMapType
go
create type cpRootMapType as Table(
RootId1 int
, RootId2 int
)
go
drop procedure if exists spMapRoot2toRoot1
go
create procedure spMapRoot2toRoot1
(
#map cpRootMapType Readonly
)
as
update linkTable set root = root1
from linktable lt
join #map m on lt.root = root2
update comments set root = root1
from comments c
join #map m on c.root = root2
-- ever growing list of places this map would need to be applied....
-- now consolidated into one place
here is the implementation
... populate #matches
declare #map cpRootMapType
insert #map select rootid1, rootid2 from #matches
exec spMapRoot2toRoot1 #map
I like to do something similar to this (though it is still very similar to using a cursor)
[code]
-- Table variable to hold list of things that need looping
DECLARE #holdStuff TABLE (
id INT IDENTITY(1,1) ,
isIterated BIT DEFAULT 0 ,
someInt INT ,
someBool BIT ,
otherStuff VARCHAR(200)
)
-- Populate your #holdStuff with... stuff
INSERT INTO #holdStuff (
someInt ,
someBool ,
otherStuff
)
SELECT
1 , -- someInt - int
1 , -- someBool - bit
'I like turtles' -- otherStuff - varchar(200)
UNION ALL
SELECT
42 , -- someInt - int
0 , -- someBool - bit
'something profound' -- otherStuff - varchar(200)
-- Loop tracking variables
DECLARE #tableCount INT
SET #tableCount = (SELECT COUNT(1) FROM [#holdStuff])
DECLARE #loopCount INT
SET #loopCount = 1
-- While loop variables
DECLARE #id INT
DECLARE #someInt INT
DECLARE #someBool BIT
DECLARE #otherStuff VARCHAR(200)
-- Loop through item in #holdStuff
WHILE (#loopCount <= #tableCount)
BEGIN
-- Increment the loopCount variable
SET #loopCount = #loopCount + 1
-- Grab the top unprocessed record
SELECT TOP 1
#id = id ,
#someInt = someInt ,
#someBool = someBool ,
#otherStuff = otherStuff
FROM #holdStuff
WHERE isIterated = 0
-- Update the grabbed record to be iterated
UPDATE #holdAccounts
SET isIterated = 1
WHERE id = #id
-- Execute your stored procedure
EXEC someRandomSp #someInt, #someBool, #otherStuff
END
[/code]
Note that you don't need the identity or the isIterated column on your temp/variable table, i just prefer to do it this way so i don't have to delete the top record from the collection as i iterate through the loop.