您可以
UPDATE使用
IF（ mysql支持 ）或通过
CASE使RDBMS更加友好来执行一个。
UPDATE exampleSET def = IF(abc = 1, 'foo', 'bar')WHERe abc IN (1, 2) -- reason to make it more faster, doesn't go on all records
或者
UPDATE exampleSET def = CASE WHEN abc = 1 THEN 'foo' ELSE 'bar' ENDWHERe abc IN (1, 2) -- reason to make it more faster, doesn't go on all records
