Does RDS for MySQL Support Stored Procedures and Functions?

Yes.

• Stored procedures and functions are a set of SQL statements that have been compiled and stored in databases. Invoking stored procedures and functions reduces the amount of data that needs to be transmitted between databases and application servers, which improves data processing efficiency.
• Differences between stored procedures or functions:
  • A function must have a return value, but a stored procedure does not.
  • The parameters of a stored procedure can be of the IN, OUT, and INOUT type, but the parameters of a function can only be of the IN type.

For details about how to create a stored procedure and a function, see the official document.