SQL Stored Procedures for SQL Server
SQL Stored Procedures for SQL Server
SQL Server stored procedures are precompiled and stored in the database, allowing for faster execution and improved security. They are also reusable, which can save time and effort in developing complex queries or data manipulations. Here are the basic steps for creating and using stored procedures in SQL Server:
- Creating a stored procedure: To create a stored procedure, you need to use the CREATE PROCEDURE statement. Here is the basic syntax:
CREATE PROCEDURE procedure_name
@parameter1 datatype1 [= default_value1] [OUTPUT],
@parameter2 datatype2 [= default_value2] [OUTPUT],
...
AS
BEGIN
-- SQL statements to be executed
END
In this syntax, the @parameter1, @parameter2, etc. are optional input parameters for the stored procedure, with their respective datatypes and default values (if any). You can also use the OUTPUT keyword to specify that the parameter is an output parameter. The SQL statements to be executed are placed within the BEGIN and END block.
- Executing a stored procedure: To execute a stored procedure, you need to use the EXEC statement. Here is the basic syntax:
EXEC procedure_name @parameter1 = value1, @parameter2 = value2, ...
In this syntax, you need to specify the parameter values for the stored procedure, if any. If there are any output parameters, you need to declare variables to store their values.
Here is an example of a simple stored procedure that takes an input parameter and returns a result set:
CREATE PROCEDURE GetEmployeesByDepartment
@department nvarchar(50)
AS
BEGIN
SELECT EmployeeID, FirstName, LastName, Title
FROM Employees
WHERE Department = @department
END
To execute this stored procedure, you can use the following statement:
EXEC GetEmployeesByDepartment @department = 'Sales'
This will return all employees with the department name of “Sales”.
Stored procedures can also be used for more complex tasks, such as data manipulations, transaction management, error handling, and more. By using stored procedures, you can improve the performance and security of your SQL Server database, as well as make your queries more modular and reusable.