alter table tbl_name add col_name type 例如,给表增加一列weight mysql>alter table...

alter table tbl_name add col_name type 例如,给表增加一列weight mysql>alter table pet add weight int 删除列 alter table tbl_name drop col_name 例如，删除列weight： mysql>alter table pet drop weight 改变列 alter table tbl_name modify col_name type 例如，改变weight的类型： mysql> alter table pet modify weight samllint 另一种方法是： alter table tbl_name change old_col_name col_name type 例如： mysql> alter table pet change weight weight samllint 给列更名 mysql>alter table pet change weight wei 给表更名 alter table tbl_name rename new_tbl 例如，把pet表更名为animal mysql>alter table pet rename animal -alter table tbl_name add col_name type for example, to form an increase in weight mysql> alter table pet add weight int Remove Columns alter table tbl_name drop col_name For example, the deletion of column weight: mysql> alter table pet drop weight change out alter table tbl_name modify col_name type for example, the type of weight change: mysql> alter table pet modify w