The difference between oracle stored procedures and functions

The difference between Oracle stored procedures and functions: 1. Return value, stored procedures have no return values, functions have return values; 2. Usage, stored procedures are called using CALL statements, and functions can be directly called in SQL statements Use; 3. Capability, stored procedures are more suitable for executing complex business logic, and functions can be used as part of SQL statements; 4. Parameter transfer, stored procedures can accept input parameters and output parameters, etc., functions can only input parameters and return Results; 5. Transaction support; 6. Execution efficiency, etc.

The operating environment of this tutorial: Windows 10 system, Oracle version 19c, DELL G3 computer.

Oracle stored procedures and functions are two commonly used storage methods in databases. They have some differences and characteristics.

First of all, stored procedures and functions are composed of a piece of pre-written code that can be stored and called in the database. What they have in common is that they can encapsulate a series of SQL statements and logical operations, providing a more efficient and reusable database operation method.

However, stored procedures and functions differ in a few ways. Below I will explain the difference in detail from the following aspects:

Return value: Functions have return values ​​and can return calculation results to the caller for use. The stored procedure has no return value. It is mainly used to perform a series of operations, such as inserting, updating or deleting data, or executing some complex business logic.

Usage: Stored procedures are called using the CALL statement, while functions can be used directly in SQL statements.

ability: Functions can be used as part of a SQL statement and can be called in a SELECT statement to calculate results. Stored procedures are more suitable for executing complex business logic, such as triggers, batch processing and other operations.

Parameter passing: Both stored procedures and functions can accept parameters, but stored procedures can accept input parameters, output parameters and input and output parameters, while functions can only accept input parameters and return results. This means that functions can only pass results through return values, while stored procedures can pass results through parameters.

Transaction support: Stored procedures can contain transaction control statements, such as BEGIN, COMMIT, and ROLLBACK, which can manage transactions within the stored procedure. Functions cannot contain transaction control statements because the main purpose of the function is to calculate results rather than manage transactions.

effectiveness: There are also some differences in execution efficiency between stored procedures and functions. Because functions can be called directly in SQL statements, they are often more efficient than stored procedures. Stored procedures need to be called via a CALL statement and may require more resources and time.

To sum up, there are some differences between stored procedures and functions in terms of usage, return values, capabilities, parameter passing, transaction support and execution efficiency. Based on specific needs and scenarios, programmers can choose a suitable storage method to implement database operations.

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