sql和oracle的语法上有什么区别

to_char(sysdate,'yyy-mm-dd');

alter table talbe_name add DF_table_name default('男') for sex;

alter table table_name modify(sex default('男'))；

print 'aaaa'+@name;

create sequence se_id

start with 1

increment by 1

if 条件1 then

             …………;

          elsif 条件2 then

             …………;

          else

            …………;

          end if;

select ....case.....（else）....end....语句

            select stuno '学号',case

            when grade>=90 and grade<=100 then '★★★★'

            when grade>=80 and grade<90 then '★★★'

         when grade>=70 and grade<80 then '★★'

         when grade>=60 and grade<70  then '★'

            else '差'

            end as '等级' from score

            go

declare

      nums number:=&nos;--&nos表示提示传入值

          begin

            case nums

              when 100 then

                dbms_output.put_line('满分也，不错');

              when 90 then

                dbms_output.put_line('90分页很不错了');

              end case;

          end;

create Login 登陆名称 with password='登陆密码'

alter Login 登陆名称 with name='新登录名称' and password='新登录密码'

alter Login 登录名称 disable(禁用)/enable(启用)

drop Login 登录名称

create user 用户名 for/from Login 登陆名称

alter user 用户名 with name='新用户名'

drop user 用户名

grant select/update/delete/insert on 表名 to 用户名

create user 用户名

identified by 密码

default tablespace users

temporary tablespace temp

quota 10M on users

alter user 用户名 identified by 新密码

grant create session to 用户名

drop user 用户名 cascade;