????ALTER TABLE?????????????????У??????????塣

???????У?desc ??????

????????????alter table t_book rename to bbb??

????????У?alter table ???? add column ???? varchar(30)??

????????У?alter table ???? drop column ??????

???????????MySQL?? alter table bbb change nnnnn hh int??

???????????SQLServer??exec sp_rename't_student.name'??'nn'??'column'??

???????????Oracle??lter table bbb rename column nnnnn to hh int??

??????????????alter table t_book modify name varchar(22)??

????sp_rename??SQLServer ?????洢????????????????塣

????mysql???????????????

????mysql??????????????????????????mysql???????????????????????????????mysql??????е??Щ????????DELETE ??UPDATE ????????????????????

??????update???????

????UPDATE tbl_name SET ????????

????WHERE ????μ?????

????????? WHERE ?????????????????????????????е????????????????

???????磬??pet???У???????????Whistler??????????????????????????????????????

????mysql> update pet set sex=’f’ where name=” Whistler”??

??????delete????????

????DELETE ?????????????

????DELETE FROM tbl_name WHERE ????????

????WHERE ????????Щ?????????????????????????????????????????????е?????????ζ ????? DELETE ??????Σ????

??????????????????е???????????????????

??????????????????????? WHERE ???????????????????????????? SELECT ????е? WHERE ???

????mysql> delete from pet where name=”Whistler”??

????????????????????????????

????mysql>delete from pet??

???????

?????????????????SQL?????÷??????UPDATE??DELETE???????С?????????????????????Σ?????????DELETE???????????????????????????????С???