Syntax
------ 
[begin_label:] LOOP
 statement_list
END LOOP [end_label]
 
Description
----------- 
LOOP implements a simple loop construct, enabling repeated
execution
of the statement list, which consists of one or more
statements, each
terminated by a semicolon (i.e., ;) statement delimiter. The
statements
within the loop are repeated until the loop is exited;
usually this is
accomplished with a LEAVE statement.
 
A LOOP statement can be labeled. end_label cannot be given
unless
begin_label also is present. If both are present, they must
be the
same.
 
See Delimiters in the mysql client for more on delimiter
usage in the client.
 


URL: https://mariadb.com/kb/en/loop/