Given a table SALARIES, such as the one below, that has m = male and f = female values. Swap all f and m values (i.e., change all f values to m and vice versa) with a single update query and no intermediate temp table.

Id Name Sex Salary
1 A m 2500
2 B f 1500
3 C m 5500
4 D f 500

UPDATE SALARIES SET sex = CASE sex WHEN 'm' THEN 'f' ELSE 'm' END

assert(line0 == l0);

function rpls(str){
return str.toLowerCase().replace(/'/g,'').replace(/ /g, '');
}
var l0 = rpls("UPDATE SALARIES SET sex = CASE sex WHEN 'm' THEN 'f' ELSE 'm' END");