Oracle数据库表中字段ID值自动增1的问题

Oracle中没有跟MySQL一样的语句来设置自增长ID字段，需要建一个触发器来实现此功能。

一、 建表

– Create table

create table LOG

(

id INTEGER,

caption NVARCHAR2(50),

content LONG,

createtime DATE

)

tablespace TEST

pctfree 10

initrans 1

maxtrans 255

storage

(

initial 64K

next 1M

minextents 1

maxextents unlimited

);

– Add comments to the columns

comment on column LOG.id

is ‘顺序号’;

comment on column LOG.caption

is ‘日志标题’;

comment on column LOG.content

is ‘日志内容’;

comment on column LOG.createtime

is ‘创建时间’;

二、建触发器

create or replace trigger TIG_LOG_ID

before insert on LOG

for each row

declare

– local variables here

begin

Select NVL(Max(ID), 0) + 1 Into :New.ID From LOG;

end TIG_LOG_ID;