//创建一个名为TEST1的表空间
CREATE SMALLFILE TABLESPACE "TEST1" DATAFILE ‘G:\ORACLE_11G\ORADATA\ORCL\TEST1‘ SIZE 100M AUTOEXTEND ON NEXT 10M MAXSIZE UNLIMITED LOGGING EXTENT MANAGEMENT LOCAL SEGMENT SPACE MANAGEMENT AUTO; 
//创建一个名为DD的用户
-- Create the user 
create user DD
  default tablespace TEST1
  temporary tablespace TEMP
  profile DEFAULT
  password expire;
//创建一个表
-- Create table
create table T_HQ_TXL
(
  name      VARCHAR2(20) not null,
  sex       CHAR(1),
  telephone NUMBER
)
tablespace TEST
  pctfree 10
  initrans 1
  maxtrans 255;
//添加列的注释
-- Add comments to the columns 
comment on column T_HQ_TXL.name
  is ‘姓名‘;
comment on column T_HQ_TXL.sex
  is ‘性别:1-男;2-女‘;
comment on column T_HQ_TXL.telephone
  is ‘电话‘;
//创建主键约束
-- Create/Recreate primary, unique and foreign key constraints 
alter table T_HQ_TXL
  add constraint PK_HQ_TXL primary key (NAME)
  using index 
  tablespace TEST
  pctfree 10
  initrans 2
  maxtrans 255;
alter table T_HQ_TXL
  add constraint UQ_HQ_SEX unique (SEX)
  using index 
  tablespace TEST
  pctfree 10
  initrans 2
  maxtrans 255;
//创建检查约束
-- Create/Recreate check constraints 
alter table T_HQ_TXL
  add constraint CHECK_SEX
  check (sex = ‘1‘ or sex = ‘2‘);
原文:http://www.cnblogs.com/shadowduke/p/4912257.html