DROPTABLEIFEXISTS`salary`;CREATETABLE`salary`(`id`int(11)NOTNULL,`name`varchar(10)NOTNULL,`sex`varchar(10)NOTNULL,`salary`int(11)NOTNULL,
PRIMARYKEY (`id`))ENGINE=InnoDBDEFAULTCHARSET=utf8mb4;-- ------------------------------ Records of salary-- ----------------------------INSERTINTO`salary`VALUES('1','A','m','2500');INSERTINTO`salary`VALUES('2','B','f','1500');INSERTINTO`salary`VALUES('3','C','m','5500');INSERTINTO`salary`VALUES('4','D','f','500');
update salary set sex =if(sex ='m','f','m');
UPDATE salary SET sex =(CASEWHEN sex ='m'THEN'f'ELSE'm'END)