How to Execute a Stored Procedure Once for Each Row Returned by Query

How do I execute a stored procedure once for each row returned by query?

use a cursor

ADDENDUM: [MS SQL cursor example]

declare @field1 int
declare @field2 int
declare cur CURSOR LOCAL for
    select field1, field2 from sometable where someotherfield is null

open cur

fetch next from cur into @field1, @field2

while @@FETCH_STATUS = 0 BEGIN

    --execute your sproc on each row
    exec uspYourSproc @field1, @field2

    fetch next from cur into @field1, @field2
END

close cur
deallocate cur

in MS SQL, here's an example article

note that cursors are slower than set-based operations, but faster than manual while-loops; more details in this SO question

ADDENDUM 2: if you will be processing more than just a few records, pull them into a temp table first and run the cursor over the temp table; this will prevent SQL from escalating into table-locks and speed up operation

ADDENDUM 3: and of course, if you can inline whatever your stored procedure is doing to each user ID and run the whole thing as a single SQL update statement, that would be optimal

Execution of Stored Procedure for every row of table using string variable

You could use CURSOR to simulate FOR-EACH with stored procedure call:

DECLARE db_cursor CURSOR LOCAL FAST_FORWARD FOR 
SELECT *FROM  dbo.tesT_User;

DECLARE @name NVARCHAR(50);

OPEN db_cursor;
FETCH NEXT FROM db_cursor INTO @name;

WHILE @@FETCH_STATUS = 0  
BEGIN  
      EXEC dbo.usp_TestSP @name = @name;

      FETCH NEXT FROM db_cursor INTO @name;
END 

CLOSE db_cursor;
DEALLOCATE db_cursor;

DBFiddle Demo

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Warning:

If it would be simple function then CROSS/OUTER APPLY is a way to go.

SELECT *
FROM dbo.Test_User tu
OUTER APPLY (SELECT dbo.usp_TestSP(tu.name)) s(a);

DBFiddle Demo2

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EDIT

i want to execute this without cursor or loop, using the same logic as displayed above

DECLARE @x NVARCHAR(MAX) = 
   (SELECT string_agg(FORMATMESSAGE('EXEC dbo.usp_TestSP @name=''%s'';', name)
   ,CHAR(13)) AS r FROM dbo.test_User);
PRINT @x;
EXEC(@x);

DBFiddle Demo3

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And finally your code:

DECLARE @Query varchar(MAX);  
select @Query=STUFF((SELECT 'EXEC dbo.usp_TestSP @name=' +QUOTENAME(Name,'''') 
       + ';' from dbo.test_user
FOR XML PATH('')),1,0,'');
EXEC(@Query);

DBFiddle Demo4

What I did:

• using semicolons (;) it's very good practice
• changed datatype to VARCHAR(MAX)
• added EXEC inside SQL
• wrapped @Query with ()

SQL Call Stored Procedure for each Row 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

Call a stored procedure for each row returned by a query in MySQL

Concepts such as “loops” (for-each, while, etc) and “branching” (if-else, call, etc) are procedural and do not exist in declarative languages like SQL. Usually one can express one's desired result in a declarative way, which would be the correct way to solve this problem.

For example, if the testProc procedure that is to be called uses the given id as a lookup key into another table, then you could (and should) instead simply JOIN your tables together—for example:

SELECT ...
FROM   objects JOIN other USING (id)
WHERE  ...

Only in the extremely rare situations where your problem cannot be expressed declaratively should you then resort to solving it procedurally instead. Stored procedures are the only way to execute procedural code in MySQL. So you either need to modify your existing sproc so that it performs its current logic within a loop, or else create a new sproc that calls your existing one from within a loop:

CREATE PROCEDURE foo() BEGIN
  DECLARE done BOOLEAN DEFAULT FALSE;
  DECLARE _id BIGINT UNSIGNED;
  DECLARE cur CURSOR FOR SELECT id FROM objects WHERE ...;
  DECLARE CONTINUE HANDLER FOR NOT FOUND SET done := TRUE;

  OPEN cur;

  testLoop: LOOP
    FETCH cur INTO _id;
    IF done THEN
      LEAVE testLoop;
    END IF;
    CALL testProc(_id);
  END LOOP testLoop;

  CLOSE cur;
END

Run stored procedure for each row of a table

You can use a cursor:

DECLARE @value1 INT,
        @value2 INT,
        @value3 INT 

DECLARE cursorElement CURSOR FOR
            SELECT  value_1, value_2, value_2
            FROM    table


OPEN cursorElement
FETCH NEXT FROM cursorElement INTO @value1, @value2, @value3

WHILE ( @@FETCH_STATUS = 0 )
BEGIN
    exec spProcedure @value1, @value2, @value3

    FETCH NEXT FROM cursorElement INTO @value1, @value2, @value3
END         
CLOSE cursorElement
DEALLOCATE cursorElement

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