ORA-01779: cannot modify a column which maps to a non key-preserved table

Question

define cusname='GEORGE';
INSERT INTO (select s.prd_id, s.cus_id, s.qty_sold, s.price from sales s, customers c where s.cus_id=c.cus_id)
VALUES (102,(select cus_id from customers where upper(c_name) like '%GEORGE%'),14,(select price from product where prd_id = 102)*14)
I am getting the following error when I am trying to run the above query.
SQL Error: ORA-01779: cannot modify a column which maps to a non key-preserved table
01779. 00000 -  "cannot modify a column which maps to a non key-preserved table"
*Cause:    An attempt was made to insert or update columns of a join view which map to a non-key-preserved table.
*Action:   Modify the underlying base tables directly.
CUSTOMERS TABLE
Name   
Null   
Type        
CUS_ID 
NOT NULL
NUMBER      
C_NAME         
VARCHAR2(50)
C_LIMIT         
NUMBER      
CITY           
VARCHAR2(20)
PRODUCT TABLE
Name 
Null   
Type        
PRD_ID
NOT NULL
NUMBER      
PRICE         
NUMBER      
COST           
NUMBER      
SALES TABLE
Name   
Null   
Type  
PRD_ID 
NOT NULL
NUMBER
CUS_ID 
NOT NULL
NUMBER
QTY_SOLD         
NUMBER
PRICE             
NUMBER

Answer 1

Hi,
As the error message sugggested, INSERT directly into the sales table.  You can get the values from a sub-query that joins whatever tables are needed, including sales itself.  MERGE might be simpler and more efficient than INSERT.
I hope this answers your question.
If not, post  a little sample data (CREATE TABLE and INSERT statements, relevant columns only) for all tables involved, and also post the results you want from that data.
If you're asking about a DML statement, such as INSERT, the sample data will be the contents of the table(s) before the DML, and the results will be state of the changed table(s) when everything is finished.
Explain, using specific examples, how you get those results from that data.
Always say which version of Oracle you're using (e.g., 11.2.0.2.0).
See the forum FAQ: https://forums.oracle.com/message/9362002