13.6.4 Variables in Stored Programs

13.6.4.1 Local Variable DECLARE Syntax
13.6.4.2 Local Variable Scope and Resolution

System variables and user-defined variables can be used in stored programs, just as they can be used outside stored-program context. In addition, stored programs can use DECLARE to define local variables, and stored routines (procedures and functions) can be declared to take parameters that communicate values between the routine and its caller.

For information about the scope of local variables and how MySQL resolves ambiguous names, see Section 13.6.4.2, “Local Variable Scope and Resolution”.