i need to convert this to phpmyadmin syntax (constraint check ) (1 reply)

hi guys ...
how i can convert this code to phpmyadmin with MySQL client version: 5.0.51a ??

DISC_TYPE VARCHAR2( 20 ) ,
constraint CKC_DISC_TYPE_DISCOUNT check ( DISC_TYPE is null or ( DISC_TYPE in ('High','Medium','Low')))

thank you...