Question

create Table payment_record(
payment_record_id int NOT NULL,
payment_number Varchar(5) NOT NULL UNIQUE,
recieved_from_client Number (8,2) NOT NULL DEFAULT 0.00,
Paid_to_client Number (8,2) NOT NULL DEFAULT 0.00,
payment_date Date NOT NULL,
PRIMARY KEY(payment_record_id));

结果

SQL> create Table payment_record(
 2  payment_record_id int NOT NULL,
 3  payment_number Varchar(5) NOT NULL UNIQUE,
 4  recieved_from_client Number (8,2) NOT NULL DEFAULT 0.00,
 5  Paid_to_client Number (8,2) NOT NULL DEFAULT 0.00,
 6  payment_date Date NOT NULL,
 7  PRIMARY KEY(payment_record_id));
 recieved_from_client Number (8,2) NOT NULL DEFAULT 0.00,
                                       *
ERROR at line 4:
ORA-00907: missing right parenthesis

请问我出错了什么？我试图创建一个默认为

的表

Paid_to_client 
recieved_from_client

如果未分配值，

可以生成0.00

Answer 1

default子句应该在NOT NULL规范之前：

SQL> create Table payment_record(
 2  payment_record_id int NOT NULL,
 3  payment_number Varchar(5) NOT NULL UNIQUE,
 4  recieved_from_client Number (8,2) DEFAULT 0.00 NOT NULL,
 5  Paid_to_client Number (8,2) DEFAULT 0.00 NOT NULL,
 6  payment_date Date NOT NULL,
 7  PRIMARY KEY(payment_record_id));

Answer 2

DEFAULT在NOT NULL之前发生：

create Table payment_record(
payment_record_id int NOT NULL,
payment_number Varchar(5) NOT NULL UNIQUE,
recieved_from_client Number (8,2) DEFAULT 0.00 NOT NULL,
Paid_to_client Number (8,2) DEFAULT 0.00 NOT NULL ,
payment_date Date NOT NULL,
PRIMARY KEY(payment_record_id));

Answer 3

您必须在列约束之前使用默认值，例如not null。对于reference

DEFAULT值的问题

3 个答案: