Oracle's stored procedures and functions are two commonly used storage objects in the database. They are a set of SQL statements that are pre-compiled and stored in the database, but there are some limitations in their use. difference. This article will delve into the differences between Oracle stored procedures and functions and provide specific code examples to demonstrate them.
1. The definition and difference between stored procedures and functions
## Stored procedures:
Function:
2. Specific examples of stored procedures and functions
CREATE OR REPLACE PROCEDURE get_employee_info (employee_id IN NUMBER, emp_name OUT VARCHAR2) IS BEGIN SELECT last_name INTO emp_name FROM employees WHERE employee_id = employee_id; END; /
DECLARE emp_name VARCHAR2(50); BEGIN get_employee_info(100, emp_name); DBMS_OUTPUT.PUT_LINE('Employee name is: ' || emp_name); END; /
CREATE OR REPLACE FUNCTION calculate_total_salary (employee_id IN NUMBER) RETURN NUMBER IS total_salary NUMBER; BEGIN SELECT sum(salary) INTO total_salary FROM salaries WHERE emp_id = employee_id; RETURN total_salary; END; /
DECLARE emp_id NUMBER := 100; total_salary NUMBER; BEGIN total_salary := calculate_total_salary(emp_id); DBMS_OUTPUT.PUT_LINE('Total salary for employee ' || emp_id || ' is: ' || total_salary); END; /
3. Applicable scenarios for stored procedures and functions
Conclusion:
Stored procedures and functions play an important role in Oracle database, but in actual applications, appropriate storage needs to be selected according to needs object. Stored procedures are suitable for handling complex business logic, while functions are better suited for calculating and returning a single value. Mastering the differences between stored procedures and functions will enable you to better perform database programming and optimization.The above is the detailed content of In-depth understanding of the differences between Oracle stored procedures and functions. For more information, please follow other related articles on the PHP Chinese website!