现有一张话务信息表，建表语句如下：
create table VIP_RECKONING
(
N_ID NUMBER(20) not null,
PHONE_NUM VARCHAR2(11),
D_ACCOUNTDATE DATE,
N_MONTHRENT NUMBER(20,2),
N_BASERATE NUMBER(20,2),
N_LONGRATE NUMBER(20,2),
N_NOTERATE NUMBER(20,2),
N_RAMBLERATE NUMBER(20,2),
N_INCREMENTRATE NUMBER(20,2),
N_OTHERRATE NUMBER(20,2),
N_PREKEEP NUMBER(20,2),
N_LIVE NUMBER(20,2)
);
comment on column VIP_RECKONING.N_ID
is '话务编号';
comment on column VIP_RECKONING.PHONE_NUM
is '手机号码';
comment on column VIP_RECKONING.D_ACCOUNTDATE
is '帐期';
comment on column VIP_RECKONING.N_MONTHRENT
is '月租费';
comment on column VIP_RECKONING.N_BASERATE
is '基本通话费';
comment on column VIP_RECKONING.N_LONGRATE
is '长途费';
comment on column VIP_RECKONING.N_NOTERATE
is '短信费';
comment on column VIP_RECKONING.N_RAMBLERATE
is '漫游费';
comment on column VIP_RECKONING.N_INCREMENTRATE
is '增值业务费';
comment on column VIP_RECKONING.N_OTHERRATE
is '其他费用';
comment on column VIP_RECKONING.N_PREKEEP
is '预存话费';
comment on column VIP_RECKONING.N_LIVE
is '余额';
