MySQL
Comment type:Line
Comment syntax:# comment
Snippet:
SELECT 1+1;     # This comment continues to the end of line

MySQL
Comment type:Line
Comment syntax:-- comment
Snippet:
SELECT 1+1;     -- This comment continues to the end of line


-- *NOTE:* MySQL double dash comments require a
-- space or control character after the double dashes

MySQL
Comment type:Block
Comment syntax:/* comment */
Snippet:
SELECT 1+

/*
this is a
multiple-line comment
*/
1;

SELECT 1 /* this is an in-line comment */ + 1;