Difference SHOW INDEX, SHOW INDEXES and SHOW KEYS in MySQL

What's the difference between the SHOW INDEX, the SHOW INDEXES and the SHOW KEYS command in MySQL? If an开发者_如何学JAVAy. I get the same results.

MySQL Doc

They are synonyms.

As per MySQL documentations it is same :-

SHOW {INDEX | INDEXES | KEYS}
    {FROM | IN} tbl_name
    [{FROM | IN} db_name]

http://dev.mysql.com/doc/refman/4.1/en/show-index.html