drop user 'username'@'host_ip_addr';
GRANT select on dbname.tablename to 'username'@'host_ip_addr' IDENTIFIED BY 'password';
show grants for username@'host_ip_addr';
drop user 'username'@'host_ip_addr';
GRANT select on dbname.tablename to 'username'@'host_ip_addr' IDENTIFIED BY 'password';
show grants for username@'host_ip_addr';