Stored procedures are widely used in SQL for encapsulating complex database operations into a single unit that can be easily called from an application. Sometimes, stored procedures need to return results back to the calling application. In this case, the procedure can be defined to return a result set or a single value using a RETURN statement.Here’s how to return results from a stored procedure in SQL with examples:
Returning a Result Set
To return a result set from a stored procedure, you can use a SELECT statement to query the database and return the result set to the calling application. Here’s an example of a stored procedure that returns a result set:
CREATE PROCEDURE get_employee_info AS BEGIN SELECT * FROM employees; END
This stored procedure simply selects all rows from the
employees table and returns the result set to the calling application. The calling application can then process the result set as needed.
Returning a Single Value
To return a single value from a stored procedure, you can use a RETURN statement to return the value to the calling application. Here’s an example of a stored procedure that returns a single value:
CREATE PROCEDURE get_employee_count AS BEGIN DECLARE @employee_count INT; SELECT @employee_count = COUNT(*) FROM employees; RETURN @employee_count; END
This stored procedure uses a DECLARE statement to define a variable
@employee_count, which is then set to the count of rows in the
employees table. The stored procedure then returns the value of
@employee_count using a RETURN statement. The calling application can retrieve this value and use it as needed.
In conclusion, returning results from a stored procedure in SQL can be accomplished using a SELECT statement to return a result set or a RETURN statement to return a single value. By using stored procedures to encapsulate complex database operations, you can improve the maintainability and security of your application.
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