Oracle的基本语法

-- 表

create table test (names varchar2(12),

                   dates date,

                   num   int,

                   dou   double);

-- 视图

create or replace view vi_test as

select * from test;
-- 同义词

create or replace synonym aa

for dbusrcard001.aa;
-- 存储过程

create or replace produce dd(v_id in employee.empoy_id%type)

as

begin

   

end

dd;
-- 函数

create or replace function ee(v_id in employee%rowtype) return varchar(15)

is

var_test varchar2(15);

begin

  return var_test;

exception when others then

   

end
-- 三种触发器的定义

create or replace trigger ff

alter delete

on test

for each row

declare

begin

   delete from test;

   if sql%rowcount < 0 or sql%rowcount is null then

      rais_replaction_err(-20004,"错误")

   end if

end

create or replace trigger gg

alter insert

on test

for each row

declare

begin

   if :old.names = :new.names then

      raise_replaction_err(-2003,"编码重复");

   end if

end

create or replace trigger hh

for update

on test

for each row

declare

begin

  if updating then

     if :old.names <> :new.names then

 reaise_replaction_err(-2002,"关键字不能修改")

     end if

  end if

end
-- 定义游标

declare

   cursor aa is

      select names,num from test;

begin

   for bb in aa

   loop

        if bb.names = "ORACLE" then

        

        end if

   end loop;

   

end
-- 速度优化，前一语句不后一语句的速度快几十倍
select names,dates 

from test,b

where test.names = b.names(+) and

      b.names is null and

      b.dates > date('2003-01-01','yyyy-mm-dd')

select names,dates

from test 

where names not in ( select names 

                       from b

                      where dates > to_date('2003-01-01','yyyy-mm-dd'))

                      
-- 查找重复记录

select names,num 

from test 

where rowid != (select max(rowid) 

                 from test b 

                where b.names = test.names and

                      b.num = test.num)

-- 查找表TEST中时间最新的前10条记录
select * from (select * from test order by dates desc) where rownum < 11
-- 序列号的产生

create sequence row_id

minvalue 1

maxvalue 9999999999999999999999

start with 1

increment by 1
insert into test values(row_id.nextval,....)