--DDL,DML

create table student(

name varchar(20),

age number(3)

)

insert into student values('Tom',18)

drop table student

delete from student where age =20

--varchar 可以儲存空字串但是varchar2儲存空字串為null；

create table person(

name varchar2(20)

age number(3)

)

insert into person values('Tom');

drop table peson

delete from student where age =20;

----------------------------------------------------------

hibernate5 struts2  spring4

---------------------------------------------------

--更新資料 左閉右開

update student set adress = trunc(dbm_random.value(1,4)) where adress is null;

update student set  adress = null;

update student set adress = '01';

where adress  = '1'

--增加列

alert table add (telephone varchar2(16))

--註釋

comment on column student.telephone is '01 市電話 02 縣電話 03 所電話'

--字元函式

Select  substr(’abcdefg’,1,3) substr,

Instr(‘abcdefg’,’c’) instr,

‘hello’ || ‘world’ concate

From table1

--數字函式

Select  to_number(‘01234’) number1,

Trunc(to_number(‘0123.678’),2) number2,

To_number(1000,’xxxx’) number3

From table1

--distinct函式

Select  count(distinct equiptype) from tables

Select count(1) from table1

--interval日期加減 next_day()函式

Select to_char(faulttime – interval ‘7’ month, ‘yyyy-mm-dd hh24:mi:ss’) intervalyear

From table1

Select faulttime today,next_day(faulttime,6) nextday from table1

--decode==case when 函式

Selct decode(position, ‘01’,’平原’，’02’,’林區’,’03’,’山區’) position

From table1

--儲存過程語法

Create or replace procedure SP_Updata_Age

(

uName in varchar,

Age int age

)

As

Begin

Update student set UserAge  = UserAge + Age where username = uname

--commit

End SP_Updata_Age

--執行

Exec SP_Updata_Age(‘jack’,1)