SQL无效标识符？

Question

我完成了输入SQL语句，但现在当我在欧米茄上运行它时，我收到了错误代码。我一直得到无效的标识符代码...

这就是我一旦用欧米茄跑它就得到了什么。

SQL> 
SQL> --question 14 
SQL> 
SQL> SELECT to_char(Avg(ProductPrice),'99,999.99') AS Avg_Price 
    2 FROM Product_mys; 
SELECT to_char(Avg(ProductPrice),'99,999.99') AS Avg_Price 
        * 
ERROR at line 1: 
ORA-00904: "PRODUCTPRICE": invalid identifier 

这些是数据被从

CREATE TABLE Dept_mys (
DeptID  Number(3)  NOT NULL, 
DeptName VARCHAR(20)  NOT NULL, 
PRIMARY KEY (DeptID) 
) ; 

CREATE TABLE Commission_mys (
CommClass CHAR(1)   NOT NULL, 
CommRate Number(2,2)  NOT NULL, 
PRIMARY KEY (CommClass) 
) ; 

CREATE TABLE Category_mys (
CatID  Number(3)  NOT NULL, 
catName VARCHAR(20)  NOT NULL, 
PRIMARY KEY (CatID) 
) ; 

CREATE TABLE SalesRep_mys (
SalesRepID NUMBER(4)  NOT NULL, 
SalesRepFName VARCHAR(20)  NOT NULL, 
SalesRepLName VARCHAR(20)  NOT NULL, 
DeptID  NUMBER(3)  NOT NULL, 
CommClass CHAR(1)   NOT NULL, 
PRIMARY KEY (SalesRepID), 
FOREIGN KEY (DeptID) REFERENCES Dept_mys, 
FOREIGN KEY (CommClass) REFERENCES Commission_mys 
) ; 

CREATE TABLE Customer_mys (
CustID  CHAR(5)   NOT NULL, 
CustFName VARCHAR(20)  NOT NULL, 
CustLName VARCHAR(20)  NOT NULL, 
CustPhone CHAR(10), 
SalesRepID NUMBER(4)  NOT NULL, 
PRIMARY KEY (CustID), 
FOREIGN KEY (SalesRepID) REFERENCES SalesRep_mys 
) ; 

CREATE TABLE Order_mys (
OrderID NUMBER(3)  NOT NULL, 
OrderDate DATE   NOT NULL, 
CustID  CHAR(5)   NOT NULL, 
PRIMARY KEY (OrderID), 
FOREIGN KEY (CustID) REFERENCES Customer_mys 
) ; 

CREATE TABLE Product_mys (
ProductID NUMBER(3)  NOT NULL, 
ProductName VARCHAR(30)  NOT NULL, 
CatID  Number(3)  NOT NULL, 
PRIMARY KEY (ProductID), 
FOREIGN KEY (CatID)  REFERENCES Category_mys 
) ; 

CREATE TABLE OrderDetail_mys (
OrderID NUMBER(3)  NOT NULL, 
ProductID NUMBER(3)  NOT NULL, 
ProductQty NUMBER(4)  NOT NULL, 
ProductPrice NUMBER(6,2)  NOT NULL, 
PRIMARY KEY (OrderID, ProductID), 
FOREIGN KEY (OrderID) REFERENCES Order_mys, 
FOREIGN KEY (ProductID)  REFERENCES Product_mys 
) ; 

Answer 1

拉着你的查询引用Sales_Rep_mys的SQL表，但在创建SalesRep_mys。所以这至少是一些问题。

同样的，Order_Detail_mys和OrderDetail_mys

看起来像那些2个修复应该这样做。