Declare variable mysql
User-defined session-scope variables, beginning with @ are not declared and are loosely and implicitly typed.  Change DECLARE to SET and drop the INT after the variable name if these are the variables you intend to use.

Program variables are declared and typed, and do not start with @.

http://dev.mysql.com/doc/refman/5.6/en/user-variables.html
http://dev.mysql.com/doc/refman/5.6/en/stored-program-variables.html