修改表名
ALTER TABLE 旧表名 RENAME AS 新表名;
ALTER TABLE teacher RENAME AS teacher1;
增加字段
ALTER TABLE teacher1 ADD age INT (11);
修改表字段
ALTER TABLE teacher1MODIFY age VARCHAR(11);
修改字段名
ALTER TABLE teacher1 CHANGE age ag1 INT(1);
删除字段
ALTER TABLE teacher1 DROP age1;
删除表
DROP TABLE IF EXISTS teacher1;
