Can Stored Procedures Be Executed for Each Table Row Without Cursors?

Executing Stored Procedures for Each Table Row without the Need for Cursors

When faced with the task of calling a stored procedure for every row in a table, it's natural to consider the approach of iterating through the rows using a cursor. However, it is possible to achieve this task without relying on cursors.

Utilizing a Set-Based Approach

In a set-based approach, we aim to find a way to perform the operation for all rows simultaneously. For example, if our goal was to update a column for every row in a table, we could leverage an UPDATE statement with an appropriate WHERE clause to modify the relevant records in one go.

Specific Case: Iterating over Row Columns

However, when dealing with scenarios where the columns of a row need to be used as input parameters for a stored procedure, a slightly different approach is required. As described in the provided answer:

• Declare and Initialize Variables: Define a variable to track which customer we're currently processing.
• Iterate over Rows: Use a WHILE loop with a SELECT statement to retrieve and update the CustomerID variable with the ID of the next customer in the table.
• Exit Condition: Set a condition to break from the loop when there are no more customers.
• Execute Stored Procedure: For each customer, call the specified stored procedure with the CustomerID parameter.

Code Sample

The provided code snippet illustrates how this approach can be implemented:

-- Declare & initialize (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

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