To loop through data in a stored procedure with LOOP, you can use the following sample syntax: 

[beginlabel:] LOOP
 sql statements
 END LOOP [endlabel]; 

To loop through data in a stored procedure with REPEAT, you can use the following sample syntax:

[beginlabel:] REPEAT
    sql statements
UNTIL condition
END REPEAT [endlabel] 

To loop through data in a stored procedure with WHILE, you can use the following sample syntax:

[beginlabel:] 
WHILE condition DO 
sql statements
END WHILE 
[end_label]