这是我的SQL Oracle脚本，我无法弄清楚为什么在尝试运行此代码时出现以下错误： 我一直在尝试运行的每个表上获得这个确切的代码。任何人都可以指出我正确的方向为什么我的代码不会运行？我已经尝试过整天研究这个问题并且无法得到它。**
Error starting at line : 12 in command -
CREATE TABLE COURSE (
CRS_CODE VARCHAR (8) NOT NULL,
CRS_DESCRIPTION VARCHAR (35) NOT NULL,
CONSTRAINT CRS_CREDIT NOT NULL,
CHECK (CRS_CREDIT IN (1,2,3,4)),
PRIMARY KEY (CRS_CODE))
Error report -
ORA-00904: : invalid identifier
00904. 00000 - "%s: invalid identifier"
*Cause:
*Action:
SQL>
**CODE BEFORE ERROR:**
/* This script file creates the following tables:*/
/*COURSE, CLASS, ENROLL, STUDENT */
set echo on;
set serveroutput on ;
/*DROP TABLE COURSE;
DROP TABLE CLASS;
DROP TABLE STUDENT;
DROP TABLE ENROLL;*/
CREATE TABLE COURSE (
CRS_CODE VARCHAR (8) NOT NULL,
CRS_DESCRIPTION VARCHAR (35) NOT NULL,
CONSTRAINT CRS_CREDIT NOT NULL,
CHECK (CRS_CREDIT IN (1,2,3,4)),
PRIMARY KEY (CRS_CODE));
CREATE TABLE CLASS (
CLASS_CODE NUMBER (5) NOT NULL,
CONSTRAINT CLASS_SECTION_Ck NOT NULL,
CLASS_TIME VARCHAR (25) NOT NULL,
CLASS_ROOM CHAR (6),
CHECK (CLASS_SECTION IN (1,2,3,4,5,6,7,8)),
PRIMARY KEY (CLASS_CODE),
FOREIGN KEY (CRS_CODE) REFERENCES COURSE (CRS_CODE));
CREATE TABLE STUDENT (
STU_NUM INTEGER NOT NULL,
STU_LNAME VARCHAR (25) NOT NULL,
STU_FNAME VARCHAR (20) NOT NULL,
STU_INIT CHAR (1),
STU_DOB DATE NOT NULL,
CONSTRAINTS STU_HRS_Ck DEFAULT 0 NOT NULL,
STU_CLASS CHARACTER(2) REFERENCES "Fr", "So", "Jr", "Gr" NOT NULL,
CONSTRAINT STU_GPA_Ck DEFAULT 0.00 NOT NULL,
STU_PHONE VARCHAR (4) NOT NULL,
PRIMARY KEY (STU_NUM),
CHECK (STU_HRS <= 0),
CHECK (STU_HRS >= 1000),
CHECK (STU_GPA BETWEEN 0.00 AND 4.00));
CREATE TABLE ENROLL (
ENROLL_GRADE_Ck VARCHAR (1) REFERENCES "A","B","C","D","F","I","W", "Z", DEFAULT Z NOT NULL,
FOREIGN KEY (STU_NUM) REFERENCES STUDENT (STU_NUM),
FOREIGN KEY (CLASS_CODE) REFERENCES CLASS (CLASS_CODE),
PRIMARY KEY (CLASS_CODE));
commit;