MySQL 8.4 Release Notes
LEAVE label
This statement is used to exit the flow control construct that
has the given label. If the label is for the outermost stored
program block, LEAVE exits the
program.
LEAVE can be used within
BEGIN ...
END or loop constructs
(LOOP,
REPEAT,
WHILE).
For an example, see Section 15.6.5.5, “LOOP Statement”.