oracle 建表sql语句

oracle 建表sql语句 ，ID为自增主键

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create table T_WAREHOUSE
(
  id                 NUMBER,
  serial_num         VARCHAR2(20),
  name               VARCHAR2(20),
  fk_bigwarehouse_id NUMBER,
  warehousetype      VARCHAR2(20)
);

-- Add comments to the table 
comment on table T_WAREHOUSE
  is '仓库';
-- Add comments to the columns 
comment on column T_WAREHOUSE.id
  is '主键';
comment on column T_WAREHOUSE.serial_num
  is '仓库编号';
comment on column T_WAREHOUSE.name
  is '仓库名称';
comment on column T_WAREHOUSE.fk_bigwarehouse_id
  is '大仓库外键编号';
comment on column T_WAREHOUSE.warehousetype
  is '仓库类型（字典表）';

--主键
ALTER TABLE T_WAREHOUSE ADD CONSTRAINT PK_T_WAREHOUSE PRIMARY KEY (ID);


--自增序列  seq开头
create sequence SEQ_T_WAREHOUSE
minvalue 1
maxvalue 9999999999999999999
start with 1
increment by 1
cache 20;
--触发器  TG开头
CREATE OR REPLACE TRIGGER TG_T_WAREHOUSE BEFORE
insert ON  T_WAREHOUSE FOR EACH ROW
begin
  select SEQ_T_WAREHOUSE.nextval into:New.ID from dual;
end;